Little Children (2006)

Continuity mistake: In the scene where May McGorvey is writing the letter to Ronnie in the hospital, the two "n's" are very close together, almost looking like the letter "m." This is shown again when Ronnie discovers it in her belongings when returning from the hospital. However, when he looks at the letter on the table after doing the dishes, it is two distinct "n's."

Narrator: Sexual tension is an elusive thing, but Kathy had pretty good radar for it. It was like someone had turned a knob to the right, and the radio station clicked in so loud and clear it almost knocked her over. Once she became aware of the connection between them, it seemed impossible that she'd missed it before.

Question: In the foursome dinner scene, Cathy checks under the table and sees something about Sarah's feet that heightens her suspicion about the affair. What does Cathy see? The camera seems to focus on Sarah's painted toenails, but I don't understand why that would arouse suspicion.