According to Alison Arngrim's book, Confessions of a Prairie Bitch: How I Survived Nellie Oleson and Learned to Love Being Hated, the writers were going to have Mary (Melissa Sue Anderson) marry John, Jr. (Radames Pera); however, Anderson personally disliked Pera, and so he was written out.
Mike Lookinland makes an appearance at the end of this episode as Patrick, the boy on train. One of Melissa Sue Anderson's first roles was as a friend of Bobby's on an episode of The Brady Bunch (1969), "Never Too Young," in which Anderson had her first on-screen kiss.
This is John Jr's final appearance in the series. He is rarely mentioned again until the season 8 episode, "Chicago", where Charles and Edwards investigate his mysterious death. A pencil picture of John is shown.
In a conversation, Charles mentions that the Edwards family moved to California.