Though Ben received a dog for Christmas, it simply vanished, never to be seen or mentioned again.
When Jason is talking on the phone with the police officer, you'll notice the address he says: "15 Robin Lane". In later episodes, the Seavers' address is fixed at 15 Robin HOOD Lane.
When Mike & Lisa turned on the lights of Jason & Maggie's bedroom, the first thing you can see is a picture of Maggie holding a baby. That picture will later be used for the theme song.
Ben's middle name is given as only Humphrey. It would be extended to Hubert Horatio Humphrey in later episodes.
The song Jason and Mike sing before they are interviewed by the news crew is "Dancing in the Dark" from Bruce Springsteen's album Born in the U.S.A..