C and I just watched the final episode of Season 1, "Operation: Annihilate" (a remarkably uninformative title). In the course of the story, James Kirk's brother Samuel Kirk and his wife Aurelan died, leaving Peter Kirk, the captain's roughly 10-year-old nephew, an orphan. I don't think we ever saw him again. I wonder why Roddenberry didn't put him into the Wesley Crusher role? Did Kirk have any other siblings who could adopt him? The whole question just seems to be dropped by the episode's end.