i got my cat (Tilly) when she was 8 weeks old and after a settling in period, she became friends with our other cat (Jasmine) who was about a year older.
Tilly had a small litter of kittens when she was 2 which we kept and before we could get her done, she managed to escape and became pregnant again. We kept one if this litter and rehomed the other 3 babies.
The first 2 babies are now 7 months old and very cure and the "baby" is now 4months old and he too is very sweet.
Tilly refuses to come into the house except to eat and even then spits and hisses at the other 4 cats in the house.
I bought a feliway on the verts advice but it hasn't worked. She is getting more aggressive and anti social.
I thought i would answer because no one has mine is the same, she has turned since she had her kitten and keeps turning on my other cat and her kitten, so i had too take the kitten away from her, but the mom is still same, i dont really know what you can do, their is not alot you can do is there, just keep her away from your other cat's