Dd aged 15 likes to take a very long time showering etc so we have set a rule of no showers after 10pm because she wouldn’t go to sleep until far too late on a school night. At 10.20 she wanted a shower, I said no, have one in the morning. She argued. I said I would wake her at 6.45 so she had time. She was very angry but agreed. It’s now nearly midnight and she is still awake. (To prove a point?) she will be very tired tomorrow and difficult to wake. She has mock exams at the moment. Should I have let her shower at 10.20?