I have a male hamster and I often keep him with a female. The got along fine in the beginning and were still getting along when she had her first litter. I separated them until the babies were old enough to find a home and then I reunited them once the babies were gone. They got along fine as if they were never separated. They had a second litter and I once again separated them. I found the babies a home and then reunited the two hamsters. This time the female started acting aggressively. Her last babies have been gone for over a month and she's still acting incredibly aggressive. My male has scabs and missing hair in places now. Is there any way to stop her aggression?