Continuity mistake: As they are playing football, when Bernie tackles Jack, you see Jack flying and landing in front of the gate. The left flag/marker is also in front of two trees. After they show everyone running over to Jack on the ground, he is lying way far left of his original position. Now the fence is behind him, the gate is gone, and the left flag is no longer in front of the trees. (00:54:48 - 00:54:56)
Continuity mistake: In the first movie, Pam says she received a fax (MCAT scores) from Greg's parents in Detroit. We see in this movie that Greg's parents have lived in Florida for many years.
Continuity mistake: When Jack is leaving the island with LJ, there is a shot with everybody screaming for him to come back and you can see the RV has driven about six feet from Bernie's slippers. Then there's two more shots which takes up about 5-6 seconds with everyone continuing to yell. But afterwards, the RV is only about 2 feet from where it was. (01:35:40)
Continuity mistake: When LJ speaks his first word, everyone runs into Roz's office where his crib is. They show it right inside of the door. Jack then blows up at Greg when he learns it is a curse word and calls an immediate family conference. Roz, Bernie and Greg leave the room. When they show the family conference, Little Jack and the crib are now gone. (01:10:55 - 01:12:05)
Continuity mistake: After Jinxy flushes Moses, in some shots the toilet seat is up beside the lid, but in the rest of the consecutive shots the seat is down. (00:36:50)
Continuity mistake: Toward the end of the movie, when Bernie is going to fight Jack, Jack's hands are on his hips then in the next shot they are down.
Continuity mistake: After Bernie accidentally kicks Greg's face and then the argument starts out front by the RV, the sun is shining when either Jack is shown and/or the Fockers and Pam from their backsides but every time the Fockers and Pam's faces are shown, there is no sun on them at all (through from that angle it should be shining on their faces).
Continuity mistake: The empty rum bottle that was placed on the table in the room during the families arguing disappears after the Fockers walk out of the room.
Continuity mistake: After Jack leaves the whole group Greg phones him and then puts the phone on the table. Its position changes between shots.
Continuity mistake: When Bernard lies in front of the RV there's a sunny spot a meter away from his head which becomes shadowy in the close-up. This swaps back and forth.
Continuity mistake: From a wide angle Greg is covering his bloody nose with the palm of his hand when Roz hugs him. A shot later, in the close-up, he covers it with the side of his hand. Then there's a different angle, and afterwards it cuts back to the first wide angle with the initial palm-of-the-hand position.
Continuity mistake: Before Bernard leg-kicks Greg, Jack's arms swap from crossed to down by his side between shots with no time to lower them.
Continuity mistake: When Bernard tells Jack that he's gonna kick his ass, Bernard's position changes between shots: sometimes he has his back to the road in front of the RV, others to a flower bed sideways to the RV.
Continuity mistake: When Greg is giving his speech-of-truth at the party he extends his right arm and points at Dina. From the opposite angle his arm is lowered.
Continuity mistake: At the party Bernard proposes a toast to his son and raises his left arm. From the opposite angle his arm is lowered.
Continuity mistake: After sticking the needle in Greg's neck Jack extends his left arm and puts some cotton on the wound. A shot later his arm is suddenly lowered.
Continuity mistake: The position of the sodium filled needle on Greg's neck changes between shots: Sometimes close to the ear, others way below.
Continuity mistake: At the party, before Dina strokes Jack's ears her left hand is either on his chest or not depending on the shot.
Continuity mistake: During Roz's massage, when she says "unleash the beast", in the close-up shot her hand disappears from Jack's shoulder.
Continuity mistake: During the massage scene, after Roz takes Jack's shirt off he raises his head. In the close-up it's pressed against the pillow, then angle cuts back to his head raised which he then lowers.
Answer: Muskrat is a "code word" they use to remind Jack to keep his temper under control.
Myridon