“Grandparents have become the family safety net, and I don’t see that changing any time soon,” said Amy Goyer, a family expert at AARP. “While they will continue to enjoy their traditional roles, including spending on gifts for grandchildren, I see them increasingly paying for the extras that parents are struggling to keep up with — sports, camps, tutoring or other educational needs, such as music lessons.”

The latest numbers are based partly on separate analyses by Goyer and Peter Francese, founder of American Demographics magazine who is now a population analyst for the MetLife Mature Market Institute. Their data were supplemented with the latest 2010 census figures as well as interviews with Census Bureau and other experts.

Currently about 5.8 million children, or nearly 8 percent of all children, are living with grandparents identified as the head of household, according to 50-state census data released Thursday. That’s up from 4.5 million, or 6.3 percent, who lived in such households in 2000.

Much of the increase in grandparent caregivers occurred later in the decade after the recession eliminated jobs for many younger people, surveys indicate.