11yo is really run down at the moment. We took him for a blood test last year and it all came back OK other than slightly low folate and he's on vitamins for that. Well he's shot up what seems like 2 feet in six months and is now about 5 foot 2/3. But he's looking very thin and I've casually weighed him tonight and he's only seven stone. That seems really low? He's also really tired at the moment and I'm not really sure how to address it without making a big deal of his weight. He eats like a horse and has a pretty good diet, probably a bit too much sugar but we've tried to address that recently too. Do you think his weight warrants a Dr's visit?