The goal of this study is to help teens with Prader-Willi Syndrome (PWS) and their families learn practical strategies for managing issues like irritability, meltdowns, and anxiety. The main objective of the study is:

To adapt current Regulating Together materials to create an outpatient group program for emotion dysregulation in Prader-Willi Syndrome (PWS) that will improve psychosocial outcomes for youth with PWS.

Up to ten children with Prader-Willi Syndrome (PWS) ages 13 to 17.5 years and their caregivers will be enrolled in the study. This study is being done to develop and test a behavior therapy to help teenagers with PWS calm their emotions. Participants will complete assessments at five time points:

Screening (T1); Week 0: Baseline visit (T2); Week 5: Post Active Treatment (T3); Week 10: 5 week follow-up (T4); and Week 15: 10 week follow-up (T5). Participants will receive 5 weeks of intervention, twice per week, following the T2 visit.

Child Participant Inclusion Criteria:

• Ages 13-17.5 years
• Confirmed genetic diagnosis of Prader-Willi Syndrome
• Fluent in spoken English
• Adolescent's use of flexible phrase speech or greater
• Meeting clinically significant emotional dysregulation criteria
• Willing to participate in weekly 90-minute group sessions
• Family is willing to keep prescribed psychiatric medication and outside behavioral interventions stable
• Parent, guardian, or legally authorized representative must provide written permission on behalf of the participant

Child Participant Exclusion Criteria:

• Initiation of new psychosocial intervention within 30 days prior to first day of treatment
• Presence of physical aggression in the adolescent directed towards a peer outside the home that resulted in injury within 30 days prior to screening
• Presence of comorbid major neuropsychiatric illness warranting other treatment approaches
• Presence of any major sensory impairment that would limit participating in the material including blindness or uncorrected hearing loss

Caregiver Inclusion Criteria:

• Age ≥ 18 years
• Lives and cares for their child with PWS for > 50% of the year
• Fluent in spoken English
• Willing to participate in twice weekly 90-minute sessions, including one virtual session weekly

Caregiver Exclusion Criteria:

-Presence of any major sensory impairment that would limit participating in the material including blindness or uncorrected hearing loss

Risk for participant identification due to small sample and narrow geographic area