Alfred had an older sister who died of unspecified causes in '83, who feasibly could have had a child that age. Childrearing decisions might have fallen to Evander Darrow when she died (or someone on the NPC dad's side if you'd rather) who could've sent him there. You'd have to make sure Kayte would be okay with that from a Darrow family background standpoint (and Hamish wouldn't step in to adopt him or anything) but if he's kind of an obnoxious shit anyways maybe that would help Uncle H be okay with the idea of shipping him off xD