During the last surgery to reconnect the girls, the clock on the wall remains the same time as the time of death of the girl that died during the first surgery; 3:42. This would be an extremely elementary mistake, particularly given that the passage of time during the separation surgery, and the subsequent time of death, was shown so explicitly. The frequency of the clock's appearance in the second surgery, and its prominence in the shots, suggest that it is not an error but rather a visual metaphor suggesting that time stopped for both patients when one died.