Continuity mistake: Near the beginning of the show, when Elizabeth and her mother are having tea before they both go off to work, for a couple of shots from in front of her, Elizabeth is holding the mug with both hands, but the shots from behind her show her holding it with one hand only.
Continuity mistake: When Carter enters Mrs. Connelly's room, we should still be able to see Lucy who was just talking to him outside the door. But when the shot shows him entering the room, there is no sign of Lucy.
Continuity mistake: When Mark and Elizabeth are coming round the corner to enter the hospital, Mark says, "Remind me again why you invited her to stay with you", and he has one arm around her and in the other hand he's holding a newspaper. As the shot changes when they go round the corner, his arm is no longer around her and both hands are on the newspaper. There was no time for the switch.
Continuity mistake: When Mark gets up from the snowbank and chases Elizabeth into the ER, his red bag is over his right arm. When the shot changes to show him entering the hospital, his bag is over his left arm - he wouldn't have had time to change it.
Continuity mistake: When young Robbie stands at the doorway of the trauma room with his father's body, the green door to the back supply cabinet is wide open and the floor is relatively clean, but when Robbie stands beside his father there are changes such as that cabinet door is closed, and the floor is littered with used latex gloves, etc. Then the cabinet door is wide open again when Carol and Luka walk in. (00:31:45)
Answer: Take care of your dad.