Here are my Carpentercest headcanons:
1: Sam gets very jealous if she sees people flirting with Tara. But it just makes sex for her and Tara even better.
2: Sometimes Sam lets Tara take control during sex. But it has nothing to do with BDSM. She just enjoys being pampered by her incredibly sexy sister.
3: Sam and Tara surprise each other with gifts. Sometimes the gifts are homemade, other times they're store brought. It's the thought that counts.
4: Tara loves having sex with Sam. It's like Sam knows exactly what she likes. And vice versa.
5: Sam and Tara have lots of movie and TV show nights when they're not busy with work &/school.
6: Chad, Mindy, and Kirby accidentally walked in on Sam & Tara kissing. The three of them were shocked and it did take them a while to get used to the Carpenter sisters being a couple.