Our Maine Coon cat is ferociously jealous of her two remaining kittens
- she's spending all her time outside & when she does come in it's
only to eat & hiss/growl/chase at the kittens.

She's coming up two-years old & came straight to us from Breeder.  We
had no other pets at the time and one three-year old daughter.  All
was well til she had a litter of seven kittens in June this year, five
of whom we were able to re-home at eight weeks.  We kept two kittens
(brother & sister) who get on very well together & are very close.

We've tried making Mother feel as welcome as possible, but she rejects
all affection from us now & goes nuts whenever she sees the other two,
either in the house or garden.  The situation is becoming
unmanageable, and we most fear the kittens turning aggressive back to
her - I can't handle having three cats fighting full time in our small
house!

Any ideas?  Seen this before?