We're probably getting another dog, a Border TerrierX puppy, going to see them tomorrow. They have boys and girls left. I've generally had girls so I'm inclined to go for a girl, DH has had boys and would prefer a boy, but we could both be persuaded around, so what is likely to be best for our current dog as his lifelong companion. He's a NSDTR (toller) who is neutered male and almost 2 and is pretty sociable with other dogs although he'll growl at dogs (fine with people) who approach when he has food or ball. He used to live with my old collie bitch who died when he was 7mths. But regularly socialises with dogs and bitches. I've only ever had 2 of mixed sex but DH has had 2 boys before. What have you all had and are there any issues I should be aware of? Whatever we get will be neutered at about 1, but I need them to get on well as I work part time and my dog comes with me, so I need them to happily share a car boot!