Reference:
I have a Westie and a Cairn\Yorkie cross they are both wonderful dogs and get on great together.....What dog do you already have?
We have a patterdale terrier who is lovely, as you say like another kid in the family....but...she is a cow (and the breed are notorious) for not coming back when you let her off in the park...but if there's another dog around she'll play and stay with them...so we were thinking of getting another anyway and figure if its a dog thats a bit better behaved it'll make things so easy