Although a considerable body of research has described the implications of parental mental illness, the perspectives of children and adolescents have rarely been addressed. In this article, I explore adolescents' experiences in everyday life, based on an action-oriented study of a Norwegian online self-help group for adolescents (aged 15 to 18) with mentally ill parents. The analysis was conducted through participant observation of the group for 2 years. The adolescents experienced a variety of difficult challenges related to their parent's mental illness: lack of information and openness; unpredictability and instability; fear; loneliness; and loss and sorrow. However, they also discussed strategies for active management of the challenges arising from the family situation. I argue that these adolescents can be understood as vulnerable as well as active participants in managing their everyday lives. I emphasize the importance of including perspectives of children and adolescents in further research so as to improve health care for families with parental mental illness.