User blog comment:Night at the Kashmir/My Theory why Sally was really sent to Fontaine's./@comment-1500935-20140923224508/@comment-1500935-20140925183633

I truly believe he was already bonded to Sally, and here's why:

At the Housewares building, Sally is calling him for help when grabbed by Booker, and names him "Mr. Bubbles." Somehow, he had already earned her trust. He probably started rampaging the first floor when Splicers tried to snatch her before Booker and Liz arrived, because some of them were hastily trying to lock him in the Toys department while others were busy trying to lure the girl out. Later, you can also see him roaming at the Bathysphere DeLuxe floor, which happens to be occupied by Atlas and his men who also took Sally with them.

Now, compare that to the scene at Suchong's clinic (considering that it may be the same Big Daddy as before). Masha and Leta are scared and call him "Mr. Monster." They also wouldn't have helped him if Elizabeth didn't tell them what to do. Sally should have behaved like them if she wasn't bonded to the Big Daddy. That said, how he reached Fontaine's is a mystery, but to quote a line from BioShock 2: "For these men, Rapture has no walls." I think what the developers tried to show in the first episode of BaS was that this Big Daddy acted like Songbird to Sally, and really went to her rescue when she was sent to the department store. The strangest part of this theory though was that Suchong never noticed that he already succeed in his objective. It still possible the bond happened just before she was sent to Fontaine's, and Suchong didn't have them long enough to notice the change in their behavior.

Now, if that Bouncer and the one at Suchong's clinic were one and the same (that unused line I quoted would tend to prove that), there is a striking difference between his interactions with Sally and the two other named Little Sisters, Masha and Leta.