A favorite of my children - so glad I could introduce granddaughter Mara to the great green room, the little bunny, and of course, the old lady whispering “hush” - which has to be spoken in.a very exact manner prescribed by my son when he was three. 
Fun to learn that this book was not allowed at the New York Public Library for a few years. 
https://www.themarysue.com/goodnight-moon-controversy-why-was-the-beloved-book-banned-for-25-years/