About 20 minutes into the movie, Jack Nicholson falls out of the car, drunk, on the right side of his face. When he gets up, a wound is on the left side of his face.
When Emma, Flap, and the children arrive in Iowa, they get out of their car and step onto the front porch of their new home. In the background, a very tall weed grows right next to their neighbor's house. A few years later, they step out on the porch again, and the same weed is growing in the same spot.
When Aurora walks up to the hotel desk after leaving Emma's hospital room, she is wearing a skirt. When she walks through the lobby into the pool area, where Tommy and Teddy threaten to get her wet, her skirt is different.
After Patsy applies Emma's makeup in the hospital, Emma hugs and kisses her before she leaves to get the boys, leaving a noticeable lipstick mark on Patsy's right cheek. It's gone in the next shot.
When Emma and Patsy are talking outside after the lunch in New York with Patsy's friends, the clouds shrouding the World Trade Center towers in the background change between shots.
When Emma gives Flap a tie, a purple tag is hanging from the sleeve of her blouse.
When Emma is standing outside the restaurant in front of the Statue of Liberty, the city background is very distorted.
During the opening credits, set in the 1950s, a 1980s station wagon is parked in a driveway in the background.
While traveling in the car in Texas, the background shows warehouses from Miller & Paine, a department store in Lincoln, Nebraska (where the scene was filmed) that didn't exist in Texas.
As the Horton family drives to Iowa, a plain road sign amid open flat fields of waiving grain indicates that they are leaving Texas. Any highway trip from Texas to Iowa would require crossing a substantial bridge over the Red River into Oklahoma.
On Aurora and Garrett's first date, they drive along the coast before lunch. They live in the River Oaks area of Houston, 50 miles from the coast. They eat lunch at Brennan's, about 3 miles from River Oaks.