Cindy Parseghian tries hard not to be bitter about losing three of her four children to a rare disease known as childhood Alzheimer's.

Few would blame her, though, if she was.

It is almost unthinkable that so much hurt would be heaped upon one mother - or that she'd find a way to make some good come of it.

Until a ticking time bomb turned up in their midst, her household was filled with "very normal children," Parseghian says.

There was her firstborn, Ara, bright and athletic, and Michael, the wannabe action hero who would march up to strangers and ask, "Will you be my friend?." Marcia, the ballerina, loved dancing so much she kept at it even in a wheelchair. And Christa, the baby of the family, had all the others "wrapped around her finger."

In 1994, Parseghian's three youngest were diagnosed with Niemann-Pick Type C, a disease that stems from a genetic inability to metabolize cholesterol. It's often referred to as childhood Alzheimer's due to a similar decline in brain function.

Michael died first, of a seizure in 1997, just shy of his 10th birthday. Christa, the youngest, died at age 10 in 2001. And Marcia, the ballerina, died in 2005, a few months after attending her junior prom at Catalina Foothills High School.

It could have crushed their mother. But buoyed by friends and family, she and her husband, Dr. Michael Parseghian, started the Ara Parseghian Medical Research Foundation. It is named for Michael's father, the renowned former Notre Dame football coach.

So far, the foundation has raised more than $37 million for research into causes and treatments.

It puts Parseghian, 56, in contact with other suffering families, which isn't easy.

"I'm the president of a club I didn't want to be a member of," she says.

"Meeting all these other families going through all their struggles, seeing their children decline over the years, it's a continuing heartache."

She credits the loving support of Tucsonans with helping her keep her sanity - the same spirit she saw after the shootings of Jan. 8.

"I wonder if we could have gotten through this if we'd lived anywhere else," she says.

Mothers Days are always bittersweet.

She spends them recalling happy memories of the children she lost, and being grateful for the love of her surviving son Ara, now 27. After spending his teens changing his siblings' feeding tubes, Ara is studying to be a doctor.

"There have been so many times when I've felt like staying in bed and pulling the covers over my head," Parseghian says. "But I don't want to be bitter.

"I try not to think about what could've been."

- Carol Ann Alaimo