I agree. Creepy perhaps. Illegal, no. Steps or in-laws are not blood kin. Greg and Marsha Brady could have had sex and it would not have been incest. I think incest pertains to blood kin.
Marsha Brady? What would Cindy think?
“Greg and Marsha Brady could have had sex and it would not have been incest. I think incest pertains to blood kin.”
You are correct. Incest pertains to sexual relationshops involving blood kin, and blood kin only - be the “relationship” parent/child or sibling/sibling or, in most (if not all) states, cousin/cousin.
I think they did, and their children had sex, and ultimately they formed a political party.