Social class mobility from grandparent to grandchild is a relatively neglected topic. Grandparents today are often healthier and more active, and have longer relationships with their grandchildren than in previous generations. We used data from the UK's Millennium Cohort Study (n = 8570) to investigate the influence of maternal and paternal grandparents' social class on the aspirations of children at age seven. Using path analysis and controlling for family income, mother's and father's education, lone motherhood, and child's ethnicity and gender, we found very small direct effects from the paternal grandmother's social class to the grandchild's classed aspirations, and small, indirect effects, via parents' class, of grandparents' class on child's classed aspirations. Multi-group analyses found few differences by ethnicity and gender. There was no evidence that, at this age, mixed-class parentage raises the aspirations of working-class children (the "sunken middle-class" hypothesis).