Why can't he get along?
We have a 6 year old Siamese, a 5 year old Himalayan and a 6 month old Snow Shoe kitten. Sammy our oldest just will not be nice to the kitten. Our himmie made friends quickly with the kitten and they get along fine but Sammie just growls and hisses, spits and makes awful Siamese noises as soon as the kitten gets anywhere near him. At times the kitten will lick his head and Sammy will lick the kitten's but most of the time Sammy is just a pain in the butt. Sam has also turned against our other cat and our other cat has been fighting with Sam too.
To be fair the kitten does like to try to play rough with Sammy (the former King of Rough House). It's all so hard to understand. Sammy had no problem accepting our other cat when we got him as a kitten.
The kitten was "fixed" this week, we are hoping that will help.
I'm about ready to trade them all in for a nice bird.