Continuity mistake: Just after Sam's friends leave the diner, he makes a comment about how slowly Rita is eating. The little girl in the booth behind Sam reaches for her drink in 2 consecutive shots (presumably only a second apart).
Continuity mistake: When Rita comes to Sam's workplace her car gets towed away. The time it takes from leaving the car till it actually hangs on the hook is exactly one minute - unbelievably fast even for traffic police as efficient as in the States.
Continuity mistake: When Sam comes to visit Lucy at her foster home for the first time he comes walking down a rather steep road. Shortly before he stops close to the house he is suddenly walking uphill, and when he turns around there is only a low-lying area behind him.
Continuity mistake: When Sam takes Lucy home after she was born he is sitting in the bus with the baby on his lap. One can tell from the baby's eyebrows that it not the same as as the one used in the delivery scene and the following scene at home.
Continuity mistake: When Sam meets Rita at her office for the first time she kicks a bowl with candies from a coffee table. The way this bowl is balanced at the edge of the table before she kicks it changes from shot to shot.
Dakota Fanning's younger sister Elle makes her film debut, portraying Lucy at age 2. Incidentally, both Dakota and Elle go by their middle names; Dakota's full name is Hannah Dakota Fanning while Elle is Mary Elle Fanning.