Son might be getting a Shitsu. Need Advice

my first dog is a male shih tzu. they are really good family dogs. and since your son's uncle is the breeder you will see for yourselves the living conditions of the puppies, meaning how good is the mother dog etc. if the temperment is good like my shih tzu's, they are very very patient with children. i brought max (my dog) at a gathering with friends who brought their children. max was surrounded by kids, pulling his hair, touching, stroking him. i saw him and max was just sitting quietly. and end of the trip he was snoring in my lap all the way home! since your cats are adults, they might be the ones who might not like the new dog. but since the puppy will stay in your place with cats, he will get used to it. he might attempt to play with the cats, but other than that i don't see a shih tzu puppy getting viscious at all. he will like to play bite when he's around 3-4months old as their teeth ang growing. you just have to scold and make him stop. have lots of toys for him (sqeaky toys, rubber balls, things to chew and pull)to play instead. max now only play bites my husband but with me he cuddles or licks me. because we trained him to think that i don't like biting, i will not play with him if he bites me. i found also that my shih tzu rarely destroys stuff. but to be sure i don't leave small stuff lying around. (it's like having another baby in the house really). and i think it's a wonderful idea that you have a 10year old son when you do this. pets teach children responsibility. and i think at 10years old, your child might want to be involved in some way with the puppy's care. make simple small tasks for him. like checking if the shih tzu has water (by the way i feed mine only 2x a day breakfast and dinner), feeding the dog (which will greatly increase their bonding), some things like that. i have experienced that growing the shih tzu's hair is really tiresome work. those who "SHOW' their shih tzus even wrap the strands so they don't get tangled or destroyed. max my dog's hair, is now puppy cut a bit fluffly. he hates having ponytails and stuff but i think this is more of discipline which can be solved. shih tzus are also stubborn. in the sense that they have mood swings too. sometimes they mope around if they know you'll leave and not take them. otherwise, they dash to the door with you. but the happiest is when you come home from a trip or even from work, and they jump all around like it seems you haven't seen them in 10 years! shih tzus also live long, they are hardy dogs. they are not prone to hip problems. just make sure their eyes and eyelashes are clean because their eyes are big and are prone to catarachs in their older years. good luck!