like miss piggy and captain kirk by birth

Miss Piggy's full name is "Pigathia Lee," but she is most commonly known simply as Miss Piggy. She is a Muppet character originally from Iowa, fitting with her described background of being from a small town, likely Keystone, Iowa. Captain Kirk, the character from Star Trek, is also famously from Iowa by birth. The word described in the crossword clue "like Miss Piggy and Captain Kirk, by birth" is "IOWAN," meaning someone from Iowa, where both these characters are considered to be originally from by their fictional or character background.