Conflict with a kickboxer in MMA gym?

Now you know what a parent feels like to have a talented son ; P As others have said, you can't pressure someone into doing something they don't want to do even if you think it's for their own good. Parents have been doing that to their kids since time immemorial by forcing them to become doctors or lawyers even if the kid is more interested in music. The only way for him to realize your point is to wait and let him experience failure himself. Once he does, he'll probably remember you and come to you for help, until then just let it be. As the saying goes: "Just because you can, doesn't mean you should."