I have 3x 7 day old Serama chicks in my brooder and 3x 2 day old Serama chicks in a temp' brooder. The latter are silkies and now look small compared to the other 3. I believe that they are all B class but the others are double the size. I want to mix them but am unsure whether to do this now, or to wait. But if I wait then I may be worse off as they will not know each other until they are older, and that meeting may be worse????????????? No idea what is best and No experience of this at all. Any help would be great.