The only medium size dog I had as a child was a miniture poodle. We also had standards and toys. Standards can be as small as 40 lbs...but males can be on the larger size. Now I have a giant breed, and that is not what you are looking for,so I won't even elaborate on Swissies, lol

As far as the poodles were, when I was growing up...they were raised with me and my brother since they were pups, so there were no issues. Getting a TOY poodle from a shelter, that may not have been raised with children, could be snippy with them. The miniture and standards have very loving personalities...standards in particular. They don't shed too, which is nice. Very easy to train too. Quick learners. Anyway, you may see a mix at a shelter or full bred...but reguardless, they are very nice tempermented dogs that I have had the experience of knowing and living with...I can't vouche for other breeds...but I do agree with going to the shelter and seeing which dog picks you and your kids...and which seems hesitant of young children, you would stay away from...good luck.