Objective: Medically ill children are at elevated risk for mental health issues ( Blackman, Gurka, Gurka, & Oliver, 2011 ), which can negatively affect health status ( DeMore, Adams, Wilson, & Hogan, 2005 ; Johnston & Martin-Herz, 2010 ). Given that children from diverse racial/ethnic backgrounds are disproportionately impacted by medical conditions ( Mehta, Lee, & Ylitalo, 2013 ) and experience marked mental health care disparities ( Marrast, Himmelstein, & Woolhandler, 2016 ), innovative interventions are necessary for meeting the needs of underserved families. Methods: The current study presents an adaptation of parent-child interaction therapy (PCIT) for medical settings that seeks to reduce barriers to care among underserved children with medical conditions and their families. We present outcomes from a case series of bedside PCIT among 5 low–socioeconomic status, medically ill children (3–6 years old; 2 Hispanic, 1 Black, 2 non-Hispanic White) exhibiting medical trauma and disruptive behavior. Main adaptations to standard PCIT included flexible setting delivery, psychoeducation on parenting a medically ill child, and modification of time-out based on child capacity. Results: All families completed treatment and demonstrated reliable and clinically meaningful change in child traumatic stress, child disruptive behavior, and parenting stress. Systematic behavioral observations also indicated improved parenting practices. Conclusions: Results suggest that PCIT can be adapted for medical settings and has the potential to address care disparities among diverse, low–socioeconomic status families impacted by pediatric medical illness. Continued research on bedside PCIT will further elucidate the feasibility and effectiveness of this adaptation, as compared with standard PCIT and typical behavioral health supports in medical settings. Implications for Impact Statement The present case series of an adaptation of parent-child interaction therapy for medically ill children yieled positive child and family outcomes among five low–socioeconomic status families across a variety of medical settings. Results highlight how bedside parent-child interaction therapy could help increase access and continuity of care among underserved pediatric populations while also filling a gap in the literature regarding behavioral parent training tailored for families impacted by pediatric illness.