Besides patients' health and well-being, healthcare interventions may affect the well-being of significant others. Such 'spill over effects' in significant others may be distinguished in two distinct effects: (i) the caregiving effect and (ii) the family effect. The first refers to the welfare effects of providing informal care, i.e., the effects of caring for someone who is ill. The second refers to a direct influence of the health of a patient on others' well-being, i.e., the effects of caring about other people. Using a sample of Dutch informal caregivers we found that both effects exist and may be comparable in size. Our results, while explorative, indicate that economic evaluations adopting a societal perspective should include both the family and the caregiving effects measured in the relevant individuals.