Just saw this on ESPN and it's pretty inspiring. If you guys know the movie Jack with Robin WIlliams, it's a young boy that has what I believe is the same disease where you're body ages at an incredible rate. Very emotional piece, Josiah just loves baseball. The first link is to the full story ESPN did, but there's also a follow up video where he meets Ryan Howard and the Phillies too.
It's a 13 minute video but if you've got the time it's probably worth it.