My dog gets diarrhea from canned food and table food. I try not to give it to him, but sometimes he gets it himself-- if you know what I mean, by either getting into the garbage or sticking his head on the counter after we are done eating or eating my 2 year olds food that she gives to him.

It doesn't matter how much or how little he eats (or what food it is) he always gets it. That is the only thing we can guess that is causing it because that is the only time something like that happens.

It could be food allergy. It could be because the human food is too rich for her/him.

As for the garbage, my dog would happily help himself. I now had a lid on my garbage can that he can't get into. As for your kidlets feeding the dog, I have no advice there as I have no kidlets of my own.

Keep trying.