I have a mother cat and her 3 offspring, 2 girls and a boy. Adopted a rescued cat about 8 mos after the litter was born. The rescued cat and the boy were sweeties. The rescued cat got very ill last month and is well but suffered some brain damage I suspect. She is eating, purring and living life. Now, all the cats reject her and the boy cat who was a home body is rarely home. He comes to eat and leaves. What's up with this?? What can I do to intergrate them all???