Really excited for you!
Can't wait to read your trip report already.
Don't know if this idea will be much use but I had the same worry about my son when I went last time. I found if I just left the corridor and bathroom/vanity area light on there was just enough dark to help him nod off quickly but there was still enough light on for myself and my partner to sit down and plan our next day and have a game of cards before we went to sleep.
Have a wonderful trip!