No need to capitalize his name again. But since his age is essentialWhen a character appears f.e. 50 years later, and therefore a different actor will play him, should we capitalize his name again and write his new age again?
Yeah, fully capitalize it, preceded by OLD, ELDERLY, MIDDLE-AGED, etc.
In my opinion, the parents can be played by the same actor with different make-up, hair, clothing, etc. The kid certainly (as I'm sure you realize) has to be played by 2 different actors.