Probably the best known and most popular constant of Blue Bloods: the family dinner. Almost every episode has one, and it helps to maintain the sense of family that's really a through-line for the series. But the family dinners also take a tremendously long time to film—as long as five hours. Getting closeups and coverage of as many as nine different characters takes time, as does re-setting the table (and food) after each take in order to maintain continuity.

The actors tend to get a little stir crazy during the long shoots and react in different ways: Bridget Moynahan gets the giggles, while Donnie Wahlberg has to take a nap on a couch in the living room set next to the dining room set because he eats the prop dinner food all day long. "It's dinner, right? I gotta eat," he told Access Hollywood. Tom Selleck, on the other hand, tries to eat all the meat but uses a spit bucket for the rest of the meal.

Selleck also employs one other trick to get through the filming of the dinner scenes with his digestion intact. When he's delivering a line or the camera is otherwise trained on him, he'll often pick up a knife and start buttering his bread. This way, he doesn't eat too much food and continuity of his food props is maintained.