Benjamin and Lydia's mother-and-son time at the family cottage goes overlong because of snowing. They don't manage to leave before Stewart and Crystal arrive, bringing the newly single Regina, Oliver and his on-off girlfriend, Trisha, with them. Then comes the revelation: Benjamin had sex with Trisha while she and Oliver were on a break. Benjamin and Trisha decide not to let Oliver know about their one night stand. Then Benjamin and Oliver accidentally find a pregnancy test that belongs to one of the women. But which one?