The mother of cancer research activist Terry Fox, whose marathon cross-Canada run inspired a global fundraising effort to fight the disease, has died.

Betty Fox, who was in her early 70s, died Friday morning, her family said in a notice posted on the Terry Fox Foundation website.

Terry Fox was a young bone cancer survivor with an artificial leg who set out in 1980 on his "Marathon of Hope" to raise money and awareness about the disease. He suffered a recurrence of the disease and halted the run in Ontario after covering nearly 5,400 kilometers (3,355 miles) in 143 days.

He died in 1981 at age 22 after becoming the youngest person to be awarded the Order of Canada at that time and is considered a national hero.

Betty Fox kept her son's cancer-fighting legacy alive by organizing runs, raising funds and helping launch the research institute and foundation that promotes Terry Fox Runs across the globe.