Ted: Yeah. When did you guys even start doing that anyway?
Marshall: Like, years ago. You should know. We lived with you.
Ted: Yeah, but you always kept your toothbrush in the bedroom. Also weird, by the way.
Lily: No, we kept it in the bathroom.
Ted: No. There was only one toothbrush in the bathroom, and it was mine.
[A look of grim realization crosses Ted, Lily and Marshall's faces]
Robin: Wait. Are you saying that for eight years, all three of you shared one toothbrush?
Lily: Oh, my God.
Ted: Kill me!
Robin: I love this so much!