What exactly is the moral of the story???
So, at the beginning of the film (or very early on), we learn 2 things about Reese and Vinces' characters:
1) They don't like spending time with their families
2) They are afraid of any constraints or restrictions caused by significant commitments to each other.
It would have made much more sense if the hour or so that we invested in the middle, while they are traveling to these "Four Christmases", made significant changes in the characters that could be seen.
But at the end of the movie, we learn:
1) Neither Reese nor Vince's family has seen Reese in at least 6 months (condidering that they would be "surprised" that she was even pregnant.
2) We see nothing, other than Vince's hokey, rambling speech and the fact that they had a baby, that shows that they are more committed to each other.
I just thought it was terrible story-telling with not much resolution.
Furthermore, this story had nothing to do with Christmas. They could have called it Four Thanksgivings or Four Easters and would have had to eliminate/change maybe 10 minutes of the movie.
This movie was terrible from the start and must have written and directed by a chimp.
Sorry.