PROJECT SUMMARY/ABSTRACT Childhood brain tumor survivors are at significant risk for cognitive and social-emotional difficulties, which are associated with reduced quality of life. With a growing survivor population, efforts to offset the burden survivors endure following life-saving treatments are imperative. Nearly half of all childhood cancer diagnoses occur in children under 5 years of age. Young age at diagnosis is the most consistent risk factor for cognitive late effects due to a rapidly developing brain, and disruption to the early learning environment. Medulloblastoma is the most common metastatic brain tumor in infants, with aggressive and lengthy treatment required for cure. A primary goal of this research program is development of interventions that mitigate the impact of cancer and cancer therapies on cognitive outcomes of childhood cancer survivors. Current interventions exclusively target children 4 years and older, despite extensive evidence that influencing early cognitive development has the potential for significant clinical impact. A caregiver educational program (CEP) has been designed to improve understanding of the importance of the early learning environment on child brain development. This CEP can be combined with a set of interactive neurodevelopmental games (INDG) designed for parents to play with their children to strengthen brain pathways for specific skills, at times when each brain pathway is particularly sensitive to life experiences. Studies have shown this CEP+INDG is effective in teaching key developmental neuroscience concepts to caregivers, with significant associated improvement in parent-child interactions and child problem-solving skills. Families of infants with brain tumors are an ideal target for CEP+INDG given these children are highly vulnerable, have no research supported intervention options, and evidence for intervention efficacy. There have been no studies investigating either intervention in children undergoing cancer treatment. Accordingly, the specific aims of this study are: 1) To evaluate the feasibility and acceptability of CEP+INDG (i.e., enrollment, completion and satisfaction rates) in infants undergoing medulloblastoma treatment; 2) To estimate the magnitude of change in caregiver-child interactions (connection and reciprocity using validated behavioral coding) following intervention; and 3) To estimate the magnitude of change in cognition and social- emotional development associated with intervention. We propose a single-blind (examiner), randomized controlled trial for infants (0-36 months) undergoing medulloblastoma treatment. Participants will be randomized (2:1) to CEP+INDG or standard of care (SOC). One to two months after initiating chemotherapy, caregivers in the intervention group will participate in a tailored 60 minute CEP. They will then receive 30 text prompts over a 3 month period to access INDG on their phone; age appropriate games are selected that can be completed in any ...