Your child is moving from hobby (value to self only) to talent (value to others) if you can report something like this fictional Mother-of-an-Artist:
My 14 year old guitar playing son started making custom guitar decals over the past year for his friends, discovered that some styles are more popular than others, and is even selling a few of those on Etsy and eBay. As a result, he is interacting with a lot of other guitar players and is starting to buy and sell and fix up used guitars. Just last week, he got his first request to do the web art for a small online music store because a music composer saw his art on a student’s guitar. He still loves his music, but he seems a lot more energetic and upbeat about the future.