Approximately 18,000 children and adolescents are diagnosed with cancer each year in the United States [21]. Childhood cancer is a crisis that impacts the entire family, including the non-ill siblings, who report feeling sad, lonely, anxious; guilty about their ill sibling's cancer; and jealous of the attention toward the sibling. They feel displaced, isolated, deprived, and angry about their parents' lack of attention toward them [1, 3-5]. Early treatment (2 to 6 months after diagnosis), is an important period because the stage is being set for future parenting behavior and communication during cancer treatment, which lasts one and three years. Parental availability and open communication are key elements for building and maintaining quality parent and child relationships during school age years [15], especially when a threat such as a sibling's cancer exists. The specific aims of this pilot study are to examine: 1) Ways in which parents express their availability (i.e., physical accessibility, openness to communication, responsiveness to calls for help) to non-ill children during early cancer treatment; 2) Content and ways in which parents communicate with non-ill children about their ill sibling's cancer diagnosis and treatment; 3) Non-ill children's self-reports of their parnts' availability (i.e., physical accessibility, openness to communication, and responsiveness to calls for help); 4) How non-ill children interpret their parents' communications about the ill sibling's cancer diagnosis and treatment; and to 5) Describe and analyze the parenting challenges for non-ill children during early treatment. Ninety participants (30 school age children, 60 parents) will be recruited from a Comprehensive Cancer Center in the Pacific Northwest during early cancer treatment (2 to 6 months after diagnosis). Semi-structured interviews will be conducted separately by telephone for parents and in-person for children. Content analysis with inductive and deductive coding will be used to analyze the interview data. A standardized questionnaire will be used to measure non-ill children's self-reports of each parent's availability. Study findins will inform the design of an evidence-based intervention to assist parents and non-ill siblings manage the challenges of a sibling's cancer and improve the quality of non-ill sibling and parent relationships. Strategies that assist parents in parenting their non-ill children can have a lastin impact on the non-ill sibling's adjustment and long-term parenting relationship.