Little Sister

"Mr. Bubbles, Mr. Bubbles, are you there? Are you there? Come and give me lollies, come and bring me toffees. Teddy bears... teddy bears."

- A Little Sister, singing while harvesting ADAM at the Footlight Theater.

"Good girls gather, gather......"

- A little Sister singing in BioShock 2 Multiplayer

Little Sisters are young girls who have been genetically altered and mentally conditioned to reclaim ADAM from the corpses around Rapture. Little Sisters are almost always accompanied by a Big Daddy. They are almost completely immune to damage and have no offensive abilities. Attacking them, however, will incur the wrath of their protectors.

History
ADAM is excreted by a Sea Slug found near Rapture. However, the sea slug did not naturally produce ADAM in large enough quantities for serious research and exploitation. Brigid Tenenbaum developed a procedure whereby a sea slug was implanted in a host's stomach. After the host fed, inducing regurgitation yielded up to thirty times the amount of usable ADAM. Female children were found to be the only viable hosts (on a technical and biological level), and after implantation they were known as Little Sisters. Although Tenenbaum hoped to keep the children in a vegetative state, they had to be fully functional in order to produce ADAM. They still maintained many of the ordinary characteristics of children: laughing, playing, smiling, and singing.

Frank Fontaine used his Little Sisters Orphanage in Apollo Square as a front to obtain a supply of hosts for Tenenbaum. When that failed, Andrew Ryan's men began to take the little girls from their parents directly, promising they would become the salvation of Rapture. Naturally, Ryan told them nothing about the process through which that would occur.

Mental Conditioning
Dr. Suchong, realizing that the need for ADAM was greater than the amount produced by the Little Sisters, pioneered a way for them to recycle ADAM from the blood of dead Splicers, greatly increasing their ADAM yield. Naturally, the children were resistant to this demand. Dr. Suchong was able to mentally condition the children to have a neurological impulse to feed and made them associate the bodies of dead Splicers as "angels" to make the process more appealing for the girls. With a physical and neurological drive in place, the Little Sisters eagerly pursued harvesting of ADAM in Rapture. Like many of the objects in Rapture, the Little Sisters' needles was cobbled together out of whatever the makers could salvage: large needles, hose nozzles, and baby bottles in this case.

The Little Sisters were conditioned to see the world of Rapture very differently than the other inhabitants do. Instead of seeing the dark, deteriorated state of the city, they saw an idealized world, with rosy marble floors, pink drapings, and flowering vines growing everywhere. Little Sisters see their Big Daddies as noble golden knights, and they see Big Sisters as brides or princesses with elegant ballroom apparel. Statues appear as Big Daddies, and the "angels", which are in reality the dead bodies of Splicers, appear as bodies lying on the ground with the outline of a halo and angel wings surrounding them. Splicers themselves appear as beautiful, elegantly dressed men and women in masquerade masks. However, the little girls' world view is brought abruptly back to the grim, twisted reality of Rapture's decay whenever they are frightened or in the process of gathering from a corpse.

Pair Bonding
The ADAM coursing through their bodies made the Little Sisters virtually indestructible. However, they still had the stature and strength of small girls and would be a constant target for abduction and exploitation. Dr. Suchong conceived of partnering each Little Sister with a Big Daddy, a heavily spliced human grafted into an armored diving suit. A pheromone produced by the Big Daddy attracted the Little Sisters, and its counterpart produced by the Little Sisters drove the Big Daddies to defend them with their lives. The first successfully bonded Little Sister was Eleanor Lamb, who paired with the Alpha Series Big Daddy, Subject Delta.

The Little Sisters, because of the pheromone and Suchong's mental conditioning, are strongly attached to the Big Daddies, affectionately calling them "Mister Bubbles" or "Mister B". However, the strong bond between the pairs made the Big Daddies highly aggressive, prompting Ryan to issue public warnings against approaching any Little Sisters. When a Big Daddy is killed, its Little Sisters will stop whatever she is doing and mourn its death.

Curing the Little Sisters
Removal of the sea slug from the host under normal circumstances is fatal. Although the host does not die immediately (their heartbeat can be heard), it was likened to taking a patient off life support: their demise was inevitable. In a forced removal, a large amount of ADAM could still be obtained from the sea slug. However, Tenenbaum's constant contact with the Little Sisters and their unsuppressed childlike behavior eventually caused her to seek a way to safely remove the sea slug. In time, she was able to design a Plasmid to accomplish just that. However, the Plasmid could not reverse the mental conditioning: only time could accomplish that. Tenenbaum established a safe house for restored Little Sisters in the tunnels beneath Olympus Heights for that purpose.

Big Sisters and New Little Sisters
After the events of BioShock Tenenbaum left for the surface, taking many of the saved Little Sisters with her. However, Sofia Lamb soon came into power in Rapture and restarted the Little Sister program to supply The Rapture Family with much needed ADAM and to further her own plans. There were not enough young girls left in Rapture to supply the ADAM cycle, and many of those who remained had matured to the point that they were only useful as Big Sisters.

Thus, Lamb began a program of kidnapping young girls from the surface to convert them into Little Sisters. These new Little Sisters were kept in the Pediatric Wing of the Persephone prison colony under the watchful eye of Dr. Edward Grimes and his staff of physicians. The new girls developed a unique psychological bond with Eleanor Lamb, who could see through their eyes and control them to a certain extent.

Physical Characteristics
Each Little Sister is a young girl between the age of five and eight. In BioShock the little sisters had varying hair colors, but in BioShock 2 they are all brunette, including Cindy ingame due to time constraints preventing the developers from making her blonde. The girls are clothed in dirty dresses of various colors that reach just below their knees. All of the Little Sisters are barefoot while they explore the halls of Rapture, but due to their fast regeneration they can walk on any harsh surface without problem. The Little Sisters are nearly invulnerable to damage while they have the sea slugs within them. When one is struck her flesh will glow an unnatural golden color, showing the effects of fast regeneration due to ADAM. However, even with the fast regeneration of ADAM the girls are still vulnerable. The Little Sisters could be killed by Splicers who wanted to extract the ADAM they contained by forced removal of the sea slug (i.e harvesting). Although Little Sisters are "invincible" and able to regenerate any damage, this invincibility is not perfect. An example of this is if the Little Sister were to break her legs, forcing them at odd angles. This would heal so quickly, they would fuse at these angles. They would have to be broken repeatedly due to the small window of time before they re-heal and Little Sisters are also not immune to the pain caused.

The only attack that can effect Little Sisters is the splash damage of a grenade. When a Little Sister is in the vicinity of a thrown grenade she will become ragdollish and move with the splash impulse as she is briefly knocked unconscious, then stand back up. Little Sisters can even survive being underwater. In BioShock 2, there are two instances where the player can see Little Sisters underwater. In Pauper's Drop, a Big Sister can be seen swimming underwater with a Little Sister in her back cage outside of the large window next to The Limbo Room. Also, if the player rescued all of the Little Sisters in BioShock 2, then they are used by Eleanor to help boil away the water in the compressor of Augustus Sinclair's lifeboat. In that scene the Sisters stay underwater for a prolonged period as they boil the water.

Number of Little Sisters in Rapture
There are a total of 21 Little Sisters which can be rescued or harvested, disregarding any extra Little Sisters which may appear as a result of glitches. If the player harvests all 21 of these Little Sisters, he or she will gain a total of 3360 ADAM throughout the game. If the player rescues all of the Little Sisters, and finds all of the gifts from Dr. Tenenbaum, he or she will earn a total of 3080 ADAM. Accessing the start menu will reveal the number of Little Sisters in the player's current level, as well as their current status.
 * Welcome to Rapture: 2
 * 2 Little Sisters can be seen in one Little Sister Vent each, extremely briefly; and one Little Sister is seen for a moment, but none of them can be rescued or harvested.
 * Medical Pavilion: 2
 * Only the second Little Sister is protected by a Big Daddy.
 * Neptune's Bounty: 3
 * An extra Little Sister can sometimes be found. See Extra Little Sister Bug
 * Arcadia: 2
 * An extra Little Sister can sometimes be found. See Extra Little Sister Bug
 * Farmer's Market: 1
 * Fort Frolic: 3
 * An extra Little Sister can sometimes be found. See Extra Little Sister Bug.
 * Hephaestus: 3
 * Olympus Heights: 2
 * Apollo Square: 2
 * Point Prometheus: 3
 * Proving Grounds: N/A
 * The Little Sister which the player needs to protect is not counted because she cannot be rescued or harvested, since she is no longer implanted with a slug.
 * Fontaine: N/A
 * After fighting Fontaine, the player can only see Little Sisters coming out of their vents and stabbing Fontaine to death with their needles.

Little Sister Rewards
Every three Little Sisters rescued nets the player a reward in the form of a teddy bear clutching a present left at a nearby Gatherer's Garden. The cured Little Sister who delivered the present can sometimes be seen running to the nearest vent.

Strategy
Every three Little Sisters the player harvests will grant them 480 ADAM (160 × 3), whilst every three they save will grant them 440 (80 × 3 + 200), plus many excellent Gene tonics as well as the Hypnotize Big Daddy Plasmid, as well as a bountiful quantity of First Aid Kits or EVE Hypos.

Harvesting represents the short-term solution: Not only will the player end up with more ADAM than if they had saved the Little Sisters, but the first few levels of the game will be much easier to achieve. Coupled with the potential for sampling many different Plasmids and Gene tonics at once, this is the ideal strategy for someone playing BioShock for the first time. This path unlocks the unhappiest ending to the game.

Saving, on the other hand, is a long-term investment. While it is harder to survive the first few levels with this path, it ultimately offers greater rewards. The gene tonics and Plasmids the player receives are among the most powerful in the game and cannot be obtained otherwise. The ADAM gap between a Harvester and a Rescuer (280 ADAM in total) is also compensated by these bonuses. However, these rewards may or may not suit one's play-style (due to the benevolent nature of Dr. Tenenbaum, all of these rewards offer non-aggressive boons), so it is recommended to either look up the rewards individually or play the game as a Harvester first. This option is recommended for experienced players or for those who have already played the game. This strategy will also unlock the happiest ending in the game.

Mixing both strategies is not excluded. By both harvesting and saving the Little Sisters the player offers themselves a generous dose of ADAM, with unique Plasmids and Gene tonics to boot. Please note that the player only gets their rescue reward after saving three Little Sisters, so if one is feeling scrupulous do so in blocks of three so as to get that reward as quickly as possible. Also note that this strategy will never get the player as much ADAM as a pro-Harvester, nor as many unique rewards as a pro-Rescuer. However, with efficient planning and harvest/rescue alternation one can combine the advantages of both paths, making one's life easier during the first stages of the game while being able to use a Big Daddy as a bodyguard. This option can be taken by any type of gamer, regardless of their skill or experience level. This path will also offer the player a unique ending to the game, similar to that of the Harvester ending but less miserable. Harvesting 3 Little Sisters will gain you the Evil ending.

With a Big Daddy

 * Hurry Mr.B.
 * Hop hop Mr.B, there's no time to waste.
 * Come on Mr.B the Angels are waiting for our kisses.
 * Don’t be a slow poke Mr. B.
 * Angels don't wait for slow pokes Mr. B.
 * Scabby on my knee! (x3)
 * Three too many! (x4)
 * I can see the angels dancing in the sky.
 * Is it safe to go walking now?


 * Says random lines of a poem:
 * There's a land called Lillipoppy,
 * And living there is the Lillipop!
 * I'll go there soon with Mr. Bubbles,
 * And we'll search the place from tail to top.
 * And if we find no Tattlelambie,
 * And if I eye no Porkinot,
 * Perhaps we'll dine on ham and jammie,
 * If we can't find the Lillipop!

Alarmed

 * Help me Mr. B! It hurts! It hurts!
 * You get away!
 * That one! (points at attacker)
 * Bubbles! (points at attacker)
 * Unzip ’im, Mr. B! Unzip ‘im!
 * Too many!
 * I dont like you! (points at attacker)

When Big Daddy Is in Combat

 * Unzip him Mr. B! Unzip him!


 * Don't let him get me!


 * He hurt! He hurt!


 * You hurt my mouth!


 * Kill him! KILL HIM!!!


 * Time out! You got a time out!


 * Lets dance with them daddy!


 * Its like they're dancing Mr. B!


 * Nobody hurts my daddy!
 * Tear 'em into little bits!

Before Gathering

 * Look Mr. B, ADAM…

While Gathering

 * I like getting ADAM. Makes me feel special.
 * It's a pretty angel.

After Big Daddy Is Killed

 * No, Mr. Bubbles! (sobs) Please!
 * Wake up Mr. Bubbles!
 * Mr. Bubbles! Why aren't you moving?!
 * Get up, Mr. Bubbles! Get up!
 * Mr B! Mr B!

When Going to a Vent

 * Take me home, Bubbles!
 * Mmm, I’m ready for dream time, Mr. B.
 * Time for beady-bye Mr B.
 * My tummy is full, Mr. B.
 * Time for a nap, sweet angel.

After Being Saved

 * Thank you for helping me.
 * Thank you, mister.
 * You saved me.
 * Thank you.

In Tenenbaum's Sanctuary

 * Hey! That's Mine! (Stealing a Pep Bar)
 * Who's he?
 * He's the one who saved me. or He's the one who hurts us.
 * Dr. Tenenbaum says he'll help us!
 * Come with me!
 * There he is! [whispers] The one who will save us all.
 * He's here to help us. or Stay away from him.
 * I like him.

BioShock 2
"In the House of Upside-Down: cellar's top floor, attic's ground. In the House of Upside-Down: laughing cries, and smile's frown. In the House of Upside-Down: found is lost, and lost-is found..."

- Little Sister Song/Poem at the beginning of BioShock 2

In BioShock 2, the tactics of gaining ADAM are very similar to the first game. Once the player comes across a Little Sister, they can either Harvest her, or Adopt her. It should be noted that a Little Sister rarely carries much ADAM when first met. Instead the player can put her on their shoulders and look for an ADAM-rich corpse. This will attract the Splicers' attention, forcing the player to set up a perimeter. Once she has harvested the ADAM, the player will have two choices. They can either send her to a Little Sister Vent back to Tenenbaum or they can harvest her, as she will contain a lot more ADAM after gathering. The Little Sister will give the player ADAM every time she harvests a Splicer.

This system is meant to be an even harder choice for the player, since the potential gain from harvesting is much greater. However, by saving little sisters, the player can earn a present, including a Gene Tonic called Proud Parent, increasing the ADAM harvested per corpse by 20, and the Demanding Father tonic that increases the speed at which the Sister gathers ADAM.

Storyline
To acquire a Little Sister her Big Daddy protector must be killed first. Afterward she stalls for a few seconds then replies to the player "Mister... Mister B? It's you, you're all better again!" This is due to Eleanor Lamb's psychological affinity to the player (Big Daddy). Being the first Little Sister (in addition to her ADAM augmentation), Eleanor Lamb possesses a psychological link between all Little Sisters. This allows Eleanor's affection to the player to transfer over to every Little Sister and allows the player to adopt any Little Sister in Rapture.

Near the end of the game, Delta is captured by Sofia Lamb and is immobilized. To help him escape, Eleanor Lamb sends a Little Sister to him with a plasmid to take control of her. Upon the Little Sister injecting Delta with the needle, the player will take on the viewpoint of the Little Sister. During this, the whole level will look pristinely beautiful, since the Little Sister's mental conditioning affects her perception of the world around her. The nightmarish prison cells and environment will be completely replaced by spotless white curtains and plush red carpeting. Splicers will be replaced by masked men and women in tuxedos and ballroom dresses, blood stains by flower petals, etc.

Additionally, to the choices the player has made throughout the game, the Little Sister may see different statues throughout the level depicting Delta's actions. The only times the view will show the level how it actually is is when moving toward a Splicer held in a cell, harvesting from corpses, picking up parts of a Big Sister suit, and heading back to where Sofia Lamb was. Once Eleanor has been given suit parts, she will save or harvest the Little Sister Delta was controlling (depending on the player's actions towards the Little Sisters), returning him to his body.

The players choice of whether to save or harvest Little Sisters affects the ending of the game and how Eleanor treats the other Little Sisters.

Number of Little Sisters in Rapture
There are 12 little sisters in the game who can be rescued or harvested.


 * Adonis Luxury Resort: 3-5
 * Eleanor Lamb, as a child Little Sister, can be seen in the intro.
 * A Little Sister's eyes can be seen in a Little Sister Vent.
 * Possibly identical to the previous Little Sister, another is seen getting caught by a Big Sister
 * Another one, also possibly the previous one, is encountered in the Grand Foyer
 * One can be seen accompanied a Rumbler through a window while outside of Rapture.
 * Note: All of the above can only be interacted with by using console commands.


 * The Atlantic Express: 0


 * Ryan Amusements: 1
 * Subject Delta is forced to adopt and gather twice with this Little Sister.


 * Pauper's Drop: 2


 * Siren Alley: 3


 * Dionysus Park: 3
 * Subject Delta must deal with all 3 Little Sisters.


 * Fontaine Futuristics: 3


 * Persephone Outer: 1
 * Controlled by the player, can collect ADAM for Delta.


 * Inner Persephone: 8+
 * All of these are either harvested or saved by Eleanor Lamb.

Little Sister Rewards
A reward is hidden in a teddy bear at a nearby Gatherer's Garden for every 4 sisters rescued. A bug sometimes prevents the Little Sister from moving away until Delta is right next to her. There are three gifts total, each granted after four Little Sisters have been saved.

Strategy
While the harvest/save dilemma is still present in the sequel, a new mechanic is introduced: adoption. This section will cover the latter strategy. For information on the two other mechanics, see the previous section.


 * Each Little Sister can harvest up to two corpses each. Since ADAM is the most precious resource in the game and can only be found in (very) limited supply, it is heavily recommended to have the Little Sister harvest as many corpses as possible.


 * Each successful harvest yields 40 ADAM, meaning the player can harvest up to 80 ADAM per Sister by adoption alone. Use of the Proud Parent Tonic increases the gain from 40 to 60 ADAM per corpse, the final amount given upon harvesting or rescuing the Little Sister is unaffected.


 * When having spotted a corpse, secure the entire area: hack every machine, equip the right gene tonics (especially Proud Parent and Demanding Father, if the player has them), fill up on ammo, health and EVE, and buy enough First Aid Kits and EVE Hypos to be able to wage a small war. Having done that, take note of all the passages that lead to the corpse and devise an adapted battle plan. Next up, lay traps (Trap Rivets, Trap Spears, etc) on those passages and around the corpse. If one has any Miniature Turrets, deploy them too. If the player considers themselves sufficiently prepared, signal to the Little Sister that she can start harvesting.


 * Upon adopting a Little Sister, an icon to the middle left of the HUD will indicate the Little Sister's status: if the Little Sister is on Delta's shoulders, the icon will show a Little Sister standing in front of a Big Daddy. When the Little Sister starts harvesting, a progress bar will appear, showing how much time the player has left before the Little Sister will have finished extracting ADAM from the corpse (thus ending the waves of Splicers). When harvesting, the icon will change to a Little Sister sticking her needle into a corpse. If the Little Sister is being assaulted by a Splicer the icon will change to a vivid exclamation mark, and the progress bar will pause until the Little Sister is freed from her aggressor.


 * The best form of weaponry when dealing with multiple waves of Splicers, besides traps, is ordnance and plasmids capable of dealing very quickly with several enemies, for example the Machine Gun or the Launcher. However, it is recommended to conserve resources and use the cheapest ammunition types if possible.


 * In BioShock 2, a Rescuer can gain up to 3180 ADAM (assuming the player follows the full adoption routine for each Sister and collects every Sea Slug) while a Harvester will earn a total of 3320 ADAM, creating a gap of 140 ADAM. In the long run, this means a Harvester will be able to buy more and better plasmids, although a Rescuer will be better stocked up on resources and will have the Demanding Father tonic to boot. However, the difference isn't as marked as in the first game, and both alternatives here are equivalent.


 * If one chooses to harvest the Little Sisters after obtaining the Proud Parent gene tonic, one will earn a total of 3520 ADAM, 200 more than what a pure Harvester would receive, coupled with a few extra resources. However, doing so will prevent the player from earning the Demanding Father tonic. In the long run, it is better to save the first four Little Sisters and then switch to harvesting them, rather than do the latter from the start. Also if you choose to gain the Proud Parent gene tonic you will first gain an extra 80 ADAM and you can gather from two corpses and then harvest the Little Sister at the vent. This will maximize the ADAM output but you will receive 120 ADAM for each corpse and 160 ADAM for harvesting rather than 80 for saving. This may take longer but reach an output of 280 ADAM per Little Sister therefore you receive 1120 ADAM for four sisters after the first four Little Sisters instead of 800 ADAM.

With a Big Daddy

 * C'mon Mr. B. We'll miss the angels dancing.
 * Faster, Mr. B. Don't make me carry you!
 * Skippy skip Mr.B. Big sister doesn't like slow pokes.
 * Mr. Bubbles, come on!
 * C'mon, Mr. B. More ADAM for Big Sister.
 * Hop, hop Mr.B, our Angels will wake.
 * Recites a poem:
 * In the house of upside down
 * Cellar's top floor, attic's ground.
 * In the house of upside down
 * Laughing's cry and smile's frown.
 * In the house of upside down
 * Found is lost and lost is found.

Alarmed

 * I don't like him.
 * No, Mr. B.
 * No, No, No, No!
 * That's a bad Daddy!
 * No touching!

When Big Daddy Is in Combat

 * Unzip him Mr. B! Unzip him!
 * Don't let him get me!
 * He hurt! He hurt!
 * You hurt my mouth!
 * Kill him! KILL HIM!!!
 * Time out! You got a time out!
 * Lets dance with them daddy!
 * It's like they're dancing Mr. B!
 * Ooooooh, marshmallow! (After setting a Splicer on fire)
 * Catch! (When using telekinesis)

Found an ADAM Filled Corpse

 * Here is the angel.
 * ADAM, Daddy! Right there.
 * Look, look, look!

While Gathering

 * Angel has pretty hair, dirty hair.
 * ADAM in the oven for daddy and me.
 * Its just a little pinch, ready angel?
 * I'm a good girl, Mr. B.
 * Who wants to wake the sleeping angel? I do, I do.
 * I promise it won't even hurt, see.
 * Good girls gather, gather, gather.
 * ADAM in my pocket, pocket, pocket
 * I'm a big girl Mr. B.
 * This angel's all done now. Yay!
 * Angels remember 'mommy'. Who is that?

When Going to a Vent

 * Hidey hole daddy, I'm sleepy.
 * Dream time Mr. B.
 * I miss dream time, let's have dream time.
 * Time for beddy bye, Mr. B.
 * Almost there Mr. B.

Approached by Player (If the player is a Rescuer)

 * Daddy! You always save me from the monsters!
 * I'm telling the other girls that I have the best daddy!
 * Are we going to be together again, daddy?
 * He's nicer than other daddies.
 * Daddy, are you taking me home too?
 * I'm always safe with daddy.

Approached by Player (If the player is a Harvester)

 * Daddy! You're never gonna hurt me, right?
 * I'll be extra quiet! I won't make you upset!
 * Don't hurt me! Please!
 * Daddy's home! I've been good! Promise!
 * Where are we going? Daddy?
 * {Gasp}! Are you gonna...?!
 * Daddy isn't angry, is he?

When the Player Upgrades a Weapon

 * (Giggles) Even Daddy's toys have toys.
 * Oldie-toy, Newie-toy!

BioShock 2 Multiplayer
In the Multiplayer, Little Sisters feature in several game modes as a capture-able objective.

Multiplayer Quotes

 * Why did they hurt you Mr. Bubbles?
 * Not funny Mr. B!
 * Well, we'll play whatever you want Mr. B.
 * Fresh ADAM!
 * Who wants to gather ADAM? I do, I do. (giggles)
 * Almost done little angel. Don't cry.
 * Gather ADAM! Right Mr. Bubbles?
 * ADAM, ADAM!
 * Mmm, Marshmellow!
 * Okay. Not funny, Mr. B.
 * Crazy eyes, Crazy eyes!

Videos
Video:Bioshock Little Sister and Big Daddy Introduction|Introduction to Little Sisters Video:Bioshock - All 3 Alternate Endings|What Happens to the Little Sisters? Video:Bioshock 2: Harvesting a Little Sister Video:Bioshock 2: Rescuing a Little Sister Video:Bioshock 2:Gather's song|Nightmarish gathering song

Bugs/Glitches

 * In the PC version 1.0 of BioShock 2 if the player chooses to bind a different key for "use" they will still be prompted to press the original "use" key when adopting a Little Sister, but this will do nothing. Pressing the key that has been re-bound to "use" will allow the player to adopt a Little Sister.

Trivia

 * Early in the development of BioShock, the player was to collect ADAM directly from the sea slugs that produce it. However, the developers wanted to give the choice of harvesting ADAM more impact, so the host design went through many changes, including a small chipmunk like creature (like in the Utropolis story), but the effect was deemed too comedic. The concept of Little Sisters stemmed from the need to find a more empathetic victim for the player.
 * Originally the developers had planned that the Little Sister could be killed by physical damage,   but in the games they are nearly invulnerable. This is explained by the regenerative ability of the Sea Slugs within them. However, the little girls will still be immune to damage even after they have been rescued by the player character. Attempting to harm them as they run to the nearest vent will have no effect.
 * The "Little Sister" seen in the BioShock X06 Trailer features little to none of a Little Sister's characteristics, besides her ADAM extractor. This is most likely because the teaser presented content that was still under development.
 * When Jack first approaches the Little Sister Vent found in the Kashmir Restaurant, he can catch a glimpse of glowing eyes. The same thing occurs to Subject Delta when he first awakens in the Adonis Luxury Resort with the first vent he comes across.
 * There are three corpses of little girls found in one of the Mercury Suites apartments in BioShock, and there is a plaster-coated little girl in Cohen's Collection in Fort Frolic. Each of these are actually reused rescued Little Sister models. Interestingly, they are not affected by Telekinesis and will not bleed when struck.
 * In BioShock 2 the Little Sisters are voiced by Jodelle Ferland (who is much closer to the apparent age of the Little Sisters) with a distortion effect. Ferland is famous for her role in the Silent Hill movie.
 * Brigid Tenenbaum once wondered why they were only able to use little girls instead of boys. She was given a sarcastic answer by Fontaine that it meant one less bathroom to build in the orphanage. Despite this, in the Deco Devolution Artbook for BioShock 2, it is suggested that Little Brothers have existed in the games world, but were not represented in the games themselves. They would have been housed in the Therapy Rooms of Inner Persephone.
 * Little Sisters are the only children physically represented in Rapture. Billy Parson and Amir are two boy children mentioned in the game, although no representation of them is found. Jack, as a child, was heard on an audio diary in BioShock. And, as stated above, Little Brothers may be canon.
 * The developers originally allowed the Multiplayer characters the option to harvest or adopt the Little Sister. This was likely to gain an extra ADAM reward, and would likely only function in a gamemode which was likely removed.