Affleck appeared with Clinton at a child survival conference Thursday at Georgetown University.
Affleck is promoting his group, the Eastern Congo Initiative, and calls high death rates for children under 5 years old "abhorrent" and "unacceptable." Affleck says, "We wouldn't abide it in this country ... and we must not abide it in the world globally with our brothers and sisters."
Clinton says that saving children's lives "cannot be just a job for governments." She announced that more than 60 organizations in 40 countries have joined an effort to promote breastfeeding, vaccines and health care for children.