On August 13th, Linda Sirois, 49, gave birth to her 7-pound, 14-ounce grandson, Madden Hebert.

The Madawaska, Maine, mother of four volunteered to be her daughter's surrogate when doctors warned 25-year-old Angel Hebert that a heart condition made pregnancy unsafe for her.

"It was all pretty simple as far as I was concerned," Sirois tells the Portland Press Herald of her decision to carry her grandson for nine months, adding that this pregnancy was her easiest, with no morning sickness or complications.

Last summer, Angel and her husband, Brian Hebert, 29, were recommended to avoid pregnancy for the sake of Angel's health.

"It was pretty disappointing and we were pretty upset about it," Angel says. "But we kind of had an idea that it was a possibility and, all along, my mother was saying, 'I'm here and I can carry for you.' I guess we didn't really take her seriously."

Angel and Brian took Sirois up on her offer and it wasn't long before Sirois was successfully carrying her daughter's egg, fertilized with Brian's sperm.

"I just saw it as I was babysitting for a few months," she says. "It was their child all along. It was just a room for rent."

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The new parents call the surrogacy experience "awesome" and say little Madden is "eating like a champ and he doesn't fuss too much."

Sirois' story isn't the only one of its kind. Thanks to new fertility technologies, more mothers are stepping up to loan their child-bearing abilities to their daughters.

In February 2011, 61-year-old Kristine Casey gave birth to her grandson, Finnean Lee Connell, in Chicago.

And in February of this year, 48-year-old Sandy Lawrence of Myrtle, Missouri, gave birth to her granddaughter Mya.

"It seems like an unquestionably loving and generous thing for a family member to do," Josephine Johnston, a research scholar at the Hastings Center, a bioethics research institute, tells the Chicago Tribune.

"It's a great story to tell the child," Johnston adds. "It's one of those situations where outsiders might wonder if it's OK or healthy. But the experience of that child and his family will be that it's good. … If they treat it as good, it will be experienced that way."

While Johnston finds nothing ethically questionable about a woman giving birth to her grandchild, it's worth noting that Surrogacy.ca recommends that surrogate mothers not be over the age of 45.

"The older the person is, the more likely there will be a multiple gestation and also some health problems for the person who is carrying and the fetuses," Michele Goodwin, a law professor and medical ethicist at the University of Minnesota, tells The Jamestown Sun.

If your daughter faced infertility or serious health scares, would you volunteer to be her surrogate?

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