My oldest son is 14, and we've known that he has MD for about 8 years. His half-brother on his mom's side has a rare, aggressive infantile onset form, which led us to notice some of the more subtle signs when my son was young (facial palsy, winging of the shoulder blades). But it hasn't been until just recently that MD has actually affected his life. Suddenly his arms get tired and he has trouble washing his hair or changing a light bulb. He's having trouble with his ankle, and we ended up getting him a wheelchair at the zoo yesterday.
The hard part is really how this is affecting him emotionally. He's very independent, and now he has to ask for help. He's worried about appearing lazy. And he's afraid of ending up in a wheelchair all the time.
I just want him to know how much we all care and are happy to help him. At the same time, I don't want to make him feel like we think he's incapable. Luckily our family is very close, so I know we can get through the hard parts together.