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)
Continuity mistake: When Jack and Greg are in the motor home near the beginning of the movie, Jack is talking on the intercom mic to his family in the back, then puts it down when he is finished. But, in the following shot that shows Greg talking, you can see Jack's reflection on the window, showing him still talking into the mic. (00:13:30)
Continuity mistake: When they all first arrive at Roz and Bernie's, Jack brings LJ over in the stroller. As Bernie babbles, "Bazooka, bazooka," and LJ starts crying, the stroller's orange flap (between LJ's legs) is attached to the front harness around the boy's waist. In the previous couple of close-ups of Little Jack, the orange flap hangs down between his legs. (00:23:25)
Continuity mistake: When Greg does damage control in Roz's office by hiding things, the height of the table is about Greg's waist level - also note the wood paneling trim. In the previous shot, as Greg surveys the room, the table is a foot lower, which is also seen in other shots including when Greg enters the room, after the football game, to check on Jack and the table height is level with Greg's thighs. The entire table was deliberately raised in the close-up. (00:27:00)
Continuity mistake: During the scene when Gaylord's dad has just found out that Pam is pregnant, Bernie enters the room with a bottle of champagne. he crosses to the bed whilst removing the wire top of the cork in preparation of removing the cork. Cut to Gaylord and then back to Bernie and he is removing the wire again. (01:12:30)
Continuity mistake: When Jack places Jorge's hair in the test tube, he holds Greg's vial, and the name "Greg" is written with the first "G" beside the stopper. However, in the next shot, when he places the vials into the glass, the name is actually written the opposite way, with the last "G" beside the stopper (this is also seen earlier, when Jack inserts Greg's hair). Tape and handwriting differ as well. (01:23:20)
Continuity mistake: The time frame doesn't make sense when the kid glues his hand to the glue bottle. He turns on Scarface, which is nearly over. The Fockers and the Byrnes are still in town shopping and Little Jack smears glue all over his hands. By the time they get home from town, the glue bottle is well stuck to the hands. However, Scarface is still on and still on the last fight scene. (01:06:25 - 01:07:30)
Continuity mistake: When Pam and Greg step into the motor coach nothing is on the counter between the sink and stove. However, in the shot facing Dina there are groceries right beside the sink, at the edge of the counter, including a box of Orville Redenbocker's microwave popcorn. (00:12:20)
Continuity mistake: Jack's Tom Collins has different amounts of liquid when they are sitting by the lagoon. (00:32:20)
Continuity mistake: When Bernie tackles Jack, the ball drops at his feet, beside Jack. When the camera cuts away, the ball jumps ten feet away from Jack and Bernie moves away from both of them.
Continuity mistake: As they are all outside drinking Tom Collins', the 2 cherries in Greg's drink are at the bottom, then when he leans in to answer Jack's question about his 'sister', the cherries are now at the top of his glass. The cherries actually switch back and forth in several shots. (00:32:15 - 00:32:30)
Continuity mistake: After the baby escapes from the crib, Greg walks past it looking for him and the gate to the crib is wide open. Next shot, the gate is closed and there was no time for him to close it.
Continuity mistake: At the fondue dinner, when Roz says, "Of course not, that's Greg's foreskin," in this shot Dina holds down the album page with her left hand, as she holds the skin over the album. In the next shot facing Jack, Dina drops it and it falls beyond the open page, yet, in the next close-up the piece falls directly on the open page with the photo. (00:46:15)
Continuity mistake: When Greg sees Jack in the mirror, Jack has one hand behind his back and yet when Greg looks at Jack directly in front of him, both of Jack's hands are behind his back. (01:25:30)
Continuity mistake: The pen photos that Jack takes of Jorge do not match the ones shown on the upload screen when he sends them to the CIA, inside of the motor home. When he actually takes the pictures, he does them in rapid succession. Jorge is right in front of of the RV about a foot away and all you can see in the background is the RV since he is standing so close to it. On the uploaded photos, Jorge is at least 5-10 feet away from the RV, up on the sidewalk. He is also now at the end of the RV and the photos show the house across the street in the background. (01:05:25 - 01:16:55)
Continuity mistake: All the glasses of wine and the bottle change position and amount of liquid during the dinner scene.
Continuity mistake: In the scene where Greg comes in to his parents bedroom and they are having fun with whipped cream, there are 2 pillar candles by the door. These candles are seen in several of the shots showing Greg. The flames keep going out and relighting, but the candles are too new for the flame to be just dipping out of sight, and besides those sort of candles will often glow near the top when that happens. They must have kept blowing out between takes and the crew kept lighting them. (00:48:40)
Continuity mistake: When Greg places the luggage on counter in his apt to measure it, the front pocket double zippers are closed at the bottom of the left side. When Pam comes home and he describes the birth, both zippers are at the top center of the pocket. (00:02:20)
Continuity mistake: When Bernie is lying in front of the bus to protest Jack leaving, in the first shot his head is directly aligned with the wheel well and his feet are under the license plate. When they show Bernie getting up, he is way out to the right of the bus by a couple of feet. (01:32:11 - 01:32:36)
Continuity mistake: In the foreskin scene Greg grabs the photo album and he and his mom start a tug of war. His mom's wineglass is right next to her arm and then in the next shot it is about a foot away. (00:46:30)
Answer: Muskrat is a "code word" they use to remind Jack to keep his temper under control.
Myridon