User blog comment:Willbachbakal/Singleplayer Enemies: Big Brother/@comment-75.36.137.36-20130826092217

"the Big Brother would rely almost completely on weapons"   but still would be using some thing like tonics to get all the strength needed and things like resistance to water pressure (changes)

which are very much the same things a Big Daddy would have got  (and maybe last longer/dont use up EVE, etc...)

Perhaps they were the result of the failed attempt to accelerate  orphan boys to use for BD instead of the criminals and Fontaines experimentation mistakes/byproducts.