I think at 22 that is very forgivable... Just because the guy is built like a man and is a professional athlete doesn't mean he is a man or a professional. I know how much I changed mentally from 22-25 and from 25-30. He's kind of learning on the fly. I think what Chipper said should have a positive effect(tought love) on him, but who knows if it created a rift between the two.
Heyward is a different case. The issue appears to be that he's soft (Chipper Jones has criticized him for not playing hurt).