User blog comment:DarkSkullPirates/Ain's/Bonneys DF effects on Brook, Also Milk/@comment-972068-20121213143356

The body decaying has nothing to do with age, I'm pretty sure. Even if it did, you can't undecay what's already decayed.

Bones grow, though. Brook would probably get his bones shrunken, and his hair shorter. The skin is still missing, since it's no longer there.

And no, milk doesn't stop Ain's Devil Fruit. That's just foreshadowing Aokiji's addition to the crew.

It's canon.