Books like Happy Birthday, Sam
Pat Hutchins
Happy Birthday, Sam is 32 pages, about 35 minutes at 250 words a minute.
6 books to read next
How long each takes
Cardboard 5.3 h 
The Seasons of Arnold's Apple Tree 35 min 
The Danny and the Dinosaur Treasury 2.4 h 
Encyclopedia Brown Gets His Man 1.8 h 
Birthday Surprises 2.2 h 
Boy Next Door, the 3.2 h Bar height shows length. Estimated at 250 words a minute.