A review by pussreboots
The Princess in Black and the Bathtime Battle by Shannon Hale, Dean Hale

5.0

It takes a village to raise a child, and several kingdoms to bathe a monster. There's a particularly dirty one who refuses to wash. It's going to take the cunning and patience of several princesses in disguise to get him clean and save the day.

http://pussreboots.com/blog/2020/comments_12/princess_in_black_and_the_bathtime_battle.html