My son always has wet or mushy movements, doesn't anyone have any ideas as to why. He's 2 and we stopped giving him a lot of juice because we thought that was the cause. Then the other thing is his diet, now he isn't fat or anything, but sometimes he has fastfood like 2 times a month and eats fruit occasionally, and regular food, but we just can't figure it out. Any ideas?

Sounds like he needs some more fiber in his diet. Try this and see. Lack of fiber will make the stools looser.