Editor’s note: The phenomenon of grandparents raising their grandchildren in times of need or loss has been a recognized American family tradition since the 19th century. Now, more than 6 percent of the nation’s children reside in grandparent-headed households. This is the first of a two-part series looking at the issue.

At 73 and recovering from a twice-ruptured stomach ulcer, Ruth Brewer of Monroe, Ga., says she worries daily about death and prays it won’t happen to her anytime soon.

At least not until her granddaughter graduates high school, goes off to college and begins a life of self-sufficiency.

That day is still years away, but Brewer has a special reason for seeking divine assistance in the face of medical frailty. She is the only parent 10-year-old Nicole Cofield has ever known.

Nicole’s father died when she was 8 months old. Her brother, Joel, was 7 years old. Brewer said their mother was a drug addict with serious mental health problems and couldn’t care for them.

So Brewer took on the responsibility of raising her son’s children by adopting them, guiding Joel to top honors in high school and a coveted scholarship at the Massachusetts Institute of Technology this fall. Now, her energy is aimed at securing the same opportunity for Nicole.

“I was scared they’d be split up or I wouldn’t know where they went,” she said in a recent interview at her home. “We’re family and I’m going to do until I can’t do.”

Brewer’s resolve to again parent a family despite her senior years personifies one of America’s fastest growing and yet least recognized demographic booms: grandparents raising grandchildren.

An estimated 4.5 million children live in grandparent-headed homes in the United States, according to the U.S. Census Bureau. That’s 30 percent higher than a decade ago and translates into 6 percent of the nation’s kids. In the majority of cases, the Census data shows, the biological parents are dead or out of the picture.

Social experts call the increase and its ramifications a disturbing trend. They trace it to eight major cultural factors:

Alcohol and drug abuse.

Neglect, abuse and desertion.

Increased poverty.

Effects of AIDS disease.