You are the single mother of 3 dc ages 6, 5 and 4. You need to get away for a few hours and ask a neighbour to watch your DC. You go to a friend's house. The neighbour doesn't actually come into your house.
It is dark. Your 3 dc are on their own in the house. Your DS1 (age 6) hits DD (age 5) with a screwdriver. DD runs out crying and makes her way along the road in the dark to try and find her mummy. She falls over and grazes her knee. The police come by in a patrol car and pick DD up and DD tells the police where mummy's friend lives. The police arrive at your friend's house with DD in the back of the car and take you and DD home.
Who should be punished, DD or DS1?