I recently spoke with a medical doctor who specializes in sleep medicine, and he said that SIDS is virtually unknown in countries where children sleep with their parents. The belief is that the children's breathing is regulated by either feeling or hearing their parents' breathing. Even when the children have grown and sleep in the same room with their parents (as in Japan), the children's breathing is still regulated by the sound of their parents. It's interesting that I've heard so much opposition in this country to having an infant/child sleep in the same bed with their parents.