In the United States, 7 per cent of children (more than 5 million) have a parent who has been in prison. With a patient, sensitive approach, the US director Elizabeth Lo brings us into the midst of two generations impacted by the family-splintering effects of mass incarceration. The film focuses on a group of children as they journey overnight by bus across California to visit their mothers in prison. Part of a programme organised by the non-profit Center for Restorative Justice Works, the bus rides can be up to 10 hours each way, after which children get to spend only a few precious hours with their mothers. Intimate and heartbreaking, Mother’s Day finds fleeting moments of joy, quiet courage and enormous sorrow inside the facilities, a microcosm of a criminal justice system that reaches deep into the lives of families across the US.