My daughter, the Coast Guardian, got her first one when she was 19 and her ship was in port in Hawaii. Nothing we could do about it, although I had expressed negativity.
Our other children have been told there will be no tattoos or weird piercings while we are supporting them. We have to hope nobody turns 18 and does it anyway, because I don’t know if we’d have the fortitude to say, “Fine, you’re an adult. Two weeks notice to move out, write when you find work.”
I guess it depends on how annoyed we were with the particular child to start with ;-). If Number One Son, who is 20, show up with a tattoo or gauges (?) in his ears, I’ll have no problem putting him on the curb with his guitars, his hair products, and a sign that says “Will Do Nothing For Food.”
He made it through Pearl Harbor and the rest of the war without any tattoos.