Knock Knock by Daniel Beaty and illustrated by Bryan Collier is both beautiful and sad. A young boy plays a daily game of Knock Knock, Who’s There? with his father until the day 
his father is gone. The rest of the book is filled with ways the boy misses his father and how he can fill that void. A letter from his father shows the boy ways he can live a beautiful life into adulthood.
The story is a cathartic poem by Daniel Beaty whose father was incarcerated while he was young. Part of his story is in the author’s note. The book “offer[s] hope that every fatherless child can still create the most beautiful life possible.” Bryan Collier’s watercolour and collage illustrations underscore the text and also give it new meaning, showing the boy growing up and fulfilling his father’s words to “Knock Knock to open new doors.”
Bryan Collier won the 2014 Coretta Scott King Book Award for Knock Knock.
An Education in Books Blog 
Yes this is a deeply moving and beautifully illustrated book and you have provided a marvelous capsule review here!
I’ll be thrilled to add your site to my blogroll.
Thanks, Sam. Please do!