Thousands of people gathered in British Columbia on Saturday to remember the silver-haired mother of Canadian hero Terry Fox, who died last week after years of championing her son's dream of raising funds to fight cancer.

Betty Fox died on June 17 at the age of 73 in Chilliwack, B.C., weeks after her family announced she had fallen seriously ill.

A public funeral was held on Saturday afternoon at the Trinity United Church in Port Coquitlam. The anticipated size of the event prompted the city to prepare a secondary viewing site at a nearby community centre.

One of her grandchildren, Kirsten Fox, told the church congregation that her family has been flooded with thousands of letters of support since grandmother's death.

Kirsten described her grandmother as a caring, silly — and sometimes serious — woman who encouraged her family to hold onto their convictions.

Local and provincial politicians also arrived to pay their respects to Fox, whose efforts helped to raise more than half a billion dollars for cancer research.

"Her son planted a seed and she has just grown that vision and never given up on that," said Port Coquitlam Mayor Greg Moore.

B.C. Premier Christy Clark called Fox a "real hero" for turning the tragic death of her son into a triumph.

"Talk about tenacious…God didn't make many people like Betty Fox," she said.

Vancouver Olympic CEO John Furlong and famed wheelchair athlete Rick Hansen also attended the funeral.

Fox was best known as the mother of Terry, a cancer survivor who became a national icon in 1980 after vowing to raise money for research by running across Canada.

His Marathon of Hope ended when his cancer returned and he died on June 28, 1981.

Betty Fox kept her son's legacy alive for more than three decades by organizing runs, raising funds and playing a vital role in the creation of the Terry Fox Foundation and research institute.

"Betty was comfortable the last few weeks and months of her life, was always full of wit and rarely alone. Our wife and mom is now with Terry and joins other dear family members that predeceased her," the family said in a statement.

Her family asked that donations be made to the Terry Fox Foundation in lieu of flowers.

Born in Boissevain, Man., in 1937, Betty spent her youth on the prairie before meeting and marrying Rolland Murray Fox in Winnipeg in 1956. The couple had four children, the second-eldest of which was Terry, before moving west and settling their family in British Columbia.

Earlier this month, the Terry Fox Foundation announced that Betty was seriously ill. The Fox family has not divulged the details of her illness, except to say that it was not cancer.

Her illness and death brought forward a wave of support from well-wishers across the country.

Rick Hansen, who crossed the globe by wheelchair to raise funds for spinal cord research, said she "made unprecedented contributions to Canada and the world."

Fox's efforts at preserving her son Terry's legacy were recognized last year when she was chosen to help carry the Olympic flag into the stadium last year during the lighting of the cauldron at the Winter Olympics in Vancouver.

In January of 2011, at the unveiling of four bronze statues dedicated to Terry, she asked that a museum be erected to commemorate her son's journey.

Terry was diagnosed with bone cancer in 1977, at age 18, and doctors amputated his right leg above the knee.

On April 12, 1980, Terry set off on his Marathon of Hope in St. John's, N.L. He ran a marathon, or 42 kilometres per day, in the months ahead but was forced to stop running near Thunder Bay, Ont., after the cancer returned, this time to his lungs.

He died at age 22 on June 28, 1981.

Less than three months later, about 300,000 people took part in the first Terry Fox Run. The event was held at more than 760 sites across Canada and raised $3.5 million.

Betty and her son Darrell established the Terry Fox Foundation in 1988, which raises funds for cancer research in 28 countries by holding annual Terry Fox Runs.

Two other organizations have been set up in his name. The Terry Fox Hall of Fame opened in Toronto in 1994, which recognizes Canadians who have helped those living with physical disabilities. And the Terry Fox Research Institute opened in 2007, helping researchers to collaborate with cancer hospitals.

With files from CTV B.C. and The Canadian Press