Adding to Ferret group

Question
I have a ferret Ber who is 1half yrs old, I introduced one gill as a baby and he pulled and hauled her something awful, I kept trying to no avail, so I reared her in a big cage indoors until she was somewhat bigger, and could handle him, it worked he tried it again with her but she wasnt so feeble, one wrestling match and it was all over, the next gill I tried to introduce weeks later was attacked by the both of them so I had to repeat the same thing, put her in the cage until she got bigger, a right few weeks it took, she still had a hard time, the first gill Rosie accepted her then very quickly but Ber, no, he trailed her terribly that she pooped and wee'd everytime, I had to return her to cage several times, in the end I just had to put in her and let her work it out with him as she seemed not to surrender to his dominance but Rosie did much faster, it took ages to get them on good terms, I'd say they tolerate each other now, but at least theres no screaming matches.
Will I have to do this every time if I want to add anymore ferrets, is it because they were babies, I've read adult ferrets dont accept baby one's very well.
I'd love another one but just cant face the hassle Ber gives if this was to repeat itself? thank you Lordbless you.

Answer
It could be that Ber doesn't like babies, it also could be that he has a harder time adjusting to females.  It is honestly hard to say if you would have a repeat of the situation although we look at past behavior as a predictor of future behavior, so the chances are probably good that he will be difficult any time you introduce a new ferret to the group.