In the season 7 finale of Game of Thrones, “The Dragon and the Wolf,” we officially learn that Jon Snow (Kit Harington) is the son of Rhaegar Targaryen and Lyanna Stark, not the bastard son of Ned Stark as we’d all been told. This makes him the nephew of Daenerys Targaryen (Emilia Clarke). As it happens, we learn this just as we see Jon and Daenerys consummate their simmering romantic tension by having sex on the boat. Neither of them yet know the truth.

So HBO showed us a sex scene between two people immediately after revealing that they’re closely related. It made for somewhat awkward viewing. And apparently things were also strained behind the scenes.

Clarke and Harington recently reunited for a panel discussion at the Superhero Comic Con and Car Show in in San Antonio, Texas, where Clarke recalled filming their sex scene, per Metro. “I do remember the day, our sex scene day, and my brother was there.”

Emilia Clarke and Kit Harington reunite in adorable photo

As it ends up, Clarke’s brother worked on Game of Thrones. “My brother was in the camera department and he was on set that day,” she explained. Naturally, she had some issues with her brother being on set for her sex scene. “It was literally like, ‘Mate! You’ve got to get him out of here. He’s not allowed to be here!’”

We don’t know if Clarke’s request was heeded, but it’s good to know that Game of Thrones was committed to making things awkward between siblings both in front of and behind the camera.