Everyone has a favorite, weird little thing that they see happen on TV shows that they know would never happen in real life. Maybe, for you, it’s when characters answer the phone without saying hello, and hang up without saying goodbye. Or maybe you’re obsessed with the unusual way gifts are wrapped only on television. For me, it’s when a character’s mom starts dating their boyfriend’s dad and nobody addresses how bizarre that is.

Riverdale took this way too far when Betty and Jughead, who were dating at the time, discovered they shared a secret half-sibling. Stuff like this happens more often than you think on TV, so what gives?

To start, we turn as we always do, to 1970s television. The Bradys are the original blended family with lowkey incest vibes. While the show’s writers never dared to write storylines in which Carol’s daughters dated Mike’s sons, or even had to navigate confusing crushes, there’s no denying that the actors who played the Brady kids were into each other and couldn’t hide it on screen.

The satirical Brady Bunch movie pokes fun at the sexual tension between Greg and Marcia in particular. Whether you watched the original run of the series or, like me, caught it on Nick At Nite, we all knew what was up with those kids.

(There’s even a joke in Community Season 1 about it. “When you guys first came in we were as wholesome and healthy as the family in The Brady Bunch,” Abed says about his study group, “and now we’re as dysfunctional and incestuous as the cast of The Brady Bunch.”)