We propose a direct measure of altruism between parents and adult children, using survey data on happiness from the German Socio-Economic Panel for the years 2000-2004. The question of altruism within families has policy relevance, for example to understand whether public transfers crowd out private ones. Previous empirical evidence, based on observed transfer behavior, has failed to establish a clear consensus. Using various cross-section, panel data and instrumental variable estimators, we
find that the parents' self-reported happiness depends positively on the happiness of their adult children. A one point increase in the child's happiness has the same effect as a 15-40 percent increase in household income, depending on specification.