Books like Siblings Without Rivalry
Adele Faber, Elaine Mazlish, Elaine Marsh
Siblings Without Rivalry is 239 pages, about 4 hours 23 minutes at 250 words a minute.
12 books to read next
How long each takes
The Pain and the Great One 35 min 
Who Put That Hair in My Toothbrush? 4.0 h 
Soupy Saturdays 2.4 h 
Superfudge 3.1 h 
Dark Places 6.8 h 
My Rotten Redheaded Older Brother 35 min 
The Sight 6.7 h 
Witch & Wizard 6.2 h 
Rules 3.7 h 
Locomotion 1.8 h 
The Door to Time 4.2 h 
Judy Moody Gets Famous 2.3 h Bar height shows length. Estimated at 250 words a minute.