This tshirt was my father in laws when he was a child (1950's). Not sure if it's worth anything. My son was wearing it and it occurred to us it could be worth something....

I don't know much about Tshirts, just kind of found this site. I have another shirt to post too (superman from 1950/60ish). How can I tell if it's heat transfer?

Decent condition. Can't find any information about its worth.