I have never had a problem with animals not getting along in my house.
My bichon grew up with a kitten and they were fast friends. In fact, they ran around and played so much at times that had to put them outside because they were driving me nuts. I also had another four-year old dog when I brought my bichon home. He loved the other dog, but it took her a few weeks to really accept him, and then they became wonderful friends and they played together a lot also.
I wouldn't wait until your puppy is older. I think he would like a new little playmate tomorrow. And, I think chances for a great friendship are even better when they grow up together from a very young age.
My friend has a mini daschund. She brought him over the other day to play with my little Yorkie, and they went totally nuts and played for hours until they were both exhausted. My yorkie is a little over three months and her daschund is about 7 months old. I will say that it would be a handful to have the both of them. But "what a cute handful." And - believe me, these two little dogs would love to live together and play all the time.
I have never noticed any of my animal's friendships with one another excluding me in any way. I guess I'm just one of the pack. When my little puppy was exhausted after playing with the other little puppy ---it was my lap that he wanted to take a nap in. And, my face that he licked when he first woke up. And, when I come home from work, I have two little dogs so excited to see me that they almost can't stand it. I have lost no love letting them have each other.
Good luck! Carol Jean |