My neighbor has some (nearly full-grown) male kittens he wants to get rid
of, and I was considering adopting one. Problem is, I already have a male
cat and I suspect he's probably the father of those kittens. Someone told me
that male cats usually don't get along with their offspring, is that true?
 The other issue is house-training. The cat I have now is an adopted stray;
by the time we started letting him indoors, he was used to going outside to
take care of business and to this day, he simply goes to the door and yowls
when he needs out - no need for a litter box. So how would it work if I
brought him this 3-month old, that has never been inside? Would he adapt the
same way or would a litter box be required?
 Thanks for any advice.