Building on work undertaken at UNICEF, the article examines how children in situations of climate-related displacement, planned relocation, migration and immobility experience interconnected economic and non-economic harms. Losses and damages experienced through such (im)mobilities often cascade over time, adversely impacting children's physical and psychosocial wellbeing and access to child-critical systems and services, affecting children’s developmental paths throughout life. Failing to respond adequately risks entrenching cycles of poverty, vulnerability, inequality and loss of human capital across generations. The authors discuss why advancing child-responsive data systems, policy frameworks and participation mechanisms is crucial for decisions related to movement, relocation and adaptation interventions, where children’s views are often overlooked. Strengthening children’s inclusion is vital for better interventions and governance and for advancing intergenerational justice.