Talk:Carson Stewart/@comment-5144520-20180718214116/@comment-3452092-20180718230541

In some places, yes. At least that's my understanding. Now it's usually talking about someone who is eighteen or nineteen, but if you can adopt an eighteen or nineteen-year-old it would make sense that you could adopt someone older.

It's not technically an adoption, but my cousin sort of adopted himself into the family as an adult by legally changing his last name to that of my uncle. Obviously he was already a member of the family long before that, but he wanted to make it even more clear that he was by changing his last name, too, which might be how adopted an adult might go, name change and if anyone asks "this is my kid, sibling, cousin, etc."

People adopt grandparents all the time. It's not official by legal standards, but it might be a relationship they consider theirs for the rest of the their lives. My sister considers a guy two (or three) years younger than her as her son. He was her "freshman" in high school and that's just that.