The book by H. A. Rey, The Stars: A New Way to See Them is a perennial favorite and many adults will endorse it. It helps to visualize the constellations. (Briefly on Wikipedia here: https://en.wikipedia.org/wiki/The_Stars:_A_New_Way_to_See_Them )
Personally, unless your child is perhaps under 5 (maybe under 8), it could be a mistake to think of a “book for children.” I was given The Planets by Patrick Moore when I was ten. I still shelf it. Turn Left at Orion by Guy Consolmagno is an example of a book for learning to see the sky that will serve for decades as your child grows up. I trust that others here will have similar recommendations.