* When put on the spot to say grace, Greg simply quotes the song "Day by Day" by Godspell. You can actually hear the song playing earlier in the drugstore.
* TheReasonYouSuckSpeech that Greg gives the flight attendant.
* Many consider it in the second film, when Little Jack says "Ass....hoooole" with that expressive mouth.
* "Check it out! He's got a rubber boobie!"
* The entire dinner conversation between the Byrnses and the Fockers.
* Jack saying, "I'm not so sure Roz is really a massage therapist" while he holds up a book written by her called "Is Your Vagina Happy?"
* Greg making an ass of himself while high on truth serum.
* Greg mocking Jack on hidden camera at the end of the first two movies and his YouTube roast of Jack in the third (complete with a dance remix).