When Eric's father arrives at the hospital where Eric is being examined there is a sign above the elevator along the backwall with the placard "EMERGENCY" inserted backwards.
At about 27:30 in, there is a shot over Olivia's shoulder while the Mother talks to her. Olivia is out of focus, but a fly lands on her shoulder, walks around, and then flies away. While this is technically not a mistake things like this would usually be removed in editing.