I have an older dog that lives outside, She is a husky/ wolf mix and pretty high percentage. She prefers to be out side, and both me and my little yorkies try to cox her in sometimes but really she likes to watch for people comming and wildlife and chase off anything that moves (her temperment is just like a huge yorkie, she is vocal to new people and loves to sit on my lap and dig
...) any way she is not jelous at all of the little ones, she loves them and still doesn't want to be inside with them. I think as long as you give your bigger, outside baby the same amount of attention and love as he is used to than he should be fine.