Welcome Home, Baby-to-Be-Named-Later - S5-E1
Revealing mistake: After the baby gets her name D.J. takes baby Danielle from Jimmy and holds her. If you look closely you can tell that the baby is a doll.
Fuller House (2016)
1 revealing mistake in season 5
Other mistake: Jackson, and Max are in bed together due to a sickness. When Matt brings Tommy to them you can hear Max say "Say your line" to Jackson. (00:21:55)
Max Fuller: Holy chalupas.
Trivia: D.J. throws a life buoy onto a man which says SS Papouli on it. In Full House, Danny buys a boat and names it this in memory of the family's beloved Papouli.