Plot hole: Greg suddenly wears Jack's "breast" during the "monkey business" scene with a crying LJ. But the only time we see it is in the RV which Jack would most likely have kept locked up. How did Greg get ahold of it?
Meet the Fockers (2004)
1 plot hole - chronological order
Directed by: Jay Roach
Starring: Robert De Niro, Ben Stiller, Dustin Hoffman, Barbra Streisand, Blythe Danner, Teri Polo
Continuity mistake: Jack drops the two vials into the Tom Collins glass, while in the bathroom. At the hand-off, when he places the drink on the tray, there are no vials in the glass - there is no ice blocking them from view, just a skewer holding a maraschino cherry, a wedge of lemon, and a straw - no vials. Even Jack can't make the two vials invisible. (01:23:40)
Jack Byrnes: We use the Ferber method.
Bernie Focker: We use the Focker method. We hugged and kissed that little boy like there was no tomorrow. We Fockerized him.
Trivia: In the scene where the three men are in jail towards the end of the movie, the jailer that comes to let them out (but is stopped by Ben Stiller) actually plays a cop in the Comedy Central show "Reno 9-1-1". In fact, he may even be wearing the exact uniform he wears in the series. Also, the sheriff deputy who comes off the motorhome yelling "Look, he has rubber boobie!" is also a cop on Reno 9-1-1.
Answer: Muskrat is a "code word" they use to remind Jack to keep his temper under control.
Myridon