Sexual and gender minority (SGM) individuals, or people who identify as lesbian, gay, bisexual, transgender, genderqueer, nonbinary, or any other self-identified sexual orientation or gender identity, deal with chronic minority stress, which is associated with negative mental health outcomes such as depression, anxiety, and suicidal ideation (Medley et al., 2016; Meyer, 2003). Part of the chronic minority stressed faced by this population stems from a lack of support in their parent-child relationships (Heatherington and Lavner, 2008; Savin-Williams, 2001, 2005). The present dissertation brought attention to the inherently intergroup nature of SGM offspring's parent-child relationships by examining how SGM adult children's parent-child communication relates to their mental health, assessed by their rates of depression and anxiety, respectively. Guided by intergroup theorizing and communication accommodation theory, the present study investigated how SGM adult children's perceptions of their parents' accommodative communication behaviors "respect for divergent values and SGM identity support" related to SGM adult children's experiences of child-parent communication apprehension (CPCA), and in turn, their mental health. Parents' accommodative communication promoted more supportive, open communication environments characterized by lower levels of CPCA, which in turn promoted more positive mental health outcomes. Results demonstrated that higher levels of CPCA were associated with higher rates of epression among SGM adult children. Results highlighted the importance of respect for divergent values and identity support in creating healthy communication environments in close intergroup family relationships and fostering individual mental health outcomes. Findings shed light on how SGM adult children's parent-child communication relates to their mental health and contribute to a growing body of research examining close intergroup family relationships.