You may have guessed that Holly's cloud is a manifestation of obsessive compulsive disorder (OCD), and her therapist aims to treat it with Exposure and Response Prevention Therapy (ERP). These terms can be confusing for children having their first OCD symptoms, so The Compulsion Cloud - written by social worker Averi Ridge Castaneda - introduces both concepts in a kid-friendly manner. Ultimately, this story provides a blueprint for recovery, which shows young readers that standing up to their compulsion clouds will bring them back to the light.