By Kate Raddatz

MINNEAPOLIS (WCCO) — Three-year-old Mary made a big impact in her short life.

“She was just the most wonderful, wonderful girl,” Christine O’Keefe, Mary’s mother, said.

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Nicknamed Mary Moon by her parents, the toddler went through several rounds of chemo and a bone transplant to treat Stage 4 neuroblastoma — a cancer that starts in the adrenal glands and spreads quickly.

WCCO talked to Mary’s parents about her condition in 2009.

“There’s always hope, there’s always things to try,” said Mary’s father.

Mary died less than a week later.

“You know, losing a child, you never get over,” O’Keefe said.

Today, it’s hard to relive the loss, but it was never hard to remember what got them through the year Mary spent in and out of the hospital — the services of Child Family Life.

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“They would sit down and paint with her, and color. They would bring in Chutes and Ladders, or different types of board games,” O’Keefe said.

They started the Mary Moon Foundation, a nonprofit that funds art supplies, toys and games for the University of Minnesota Masonic Children’s Hospital.

“Within four years we have raised $100,000 now for the university,” O’Keefe said.

Their fifth annual fundraiser is on Sunday, just two days after what would have been Mary’s 10th birthday. But they’ll know she’ll be there in spirit, over the moon she’s giving back to other children.

(credit: CBS)

(credit: CBS)

“It’s kind of my way of keeping her memories alive. I’m doing something positive with the grief. I’m pouring it into helping others,” O’Keefe said.

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The Mary Moon Foundation is hosting a fundraiser and auction at the Water Park of America from 4 to 8 p.m. on Sunday. A live online auction is taking place Saturday night.

Kate Raddatz