This morning I turned off the monitor at 4am and just went to sleep as N cried, because I had not yet been to sleep and knew I would be up at 8am again. In the morning, I woke up to her just waking up and mildly fussing. When I went in to get her, I saw that she was surrounded by a halo of toys. C had heard her crying and came in to give her a selection of age-appropriate toys (every single one of them was a baby toy) to keep her calm before I came in.
What a brother! :)