It's great that you can do that with your pets. But never let your guard down too much. How many times have we heard/seen news stories where the most docile, loving family pet (usually a dog) suddenly turned on a member of their own family (usually a child)and severely hurts or kills them? It's impossible to predict how an animal will behave at all given moments, no matter how well you think you know your pet. This happened to my father with his dog...he'd had it for years. The neighbors dog came over every day and they even ate food together. One day dads dog (coincidentally a pit bull also) turned on the neighbors dog out of the blue and despite my dads efforts to get them apart, his dog killed the neighbors dog (a hound dog). My dad was devastated because this dog was like his child, but he had to euthanize the dog for the safety of all the grandkids and other pets around.
So I'm not saying you're wrong - you may put them all together and leave them forever and nothing bad EVER happen. I just didn't want folks to lose their cautious approach to this. They do say never, never, never leave your pet (dog/cat) alone in a room with your small child. For alot of folks, Our pets ARE our children too - so maybe we tend to forget that they do have the ability to attack. Whether it be another pet, or our children. Just be careful is all I'm saying - if you have them loose together in the house just keep a close eye on them, for safety's sake.