My LO is 8.5 months old and still puts everything in his mouth, though recently, he added gnawing to the list since his teeth have shown up. Where do you draw the line between what they can put in their mouths and what they can't? How do you discourage them from trying again? There are some things I'm okay with him putting in his mouth, but not chewing on, so how do I differentiate that for him, if possible.