Fellowes quoted his own creation, Downton Abbey ‘s formidable Violet Crawley (Maggie Smith), who told her son that their set doesn’t divorce. Rather, she says, “In that case, the couple are unable to see as much of each other as they would like.”

Fans of the sitcom Happy Days may recall that there were three Cunningham siblings in the first two seasons of the show. Richie (Ron Howard) and Joanie (Erin Moran) had a basketball-dribbling big brother named Chuck (Gavan O’Herlihy), but early in Season 2 in 1975, all traces of Chuck disappeared ...