For decades, millions of Americans have felt like they know Valerie Harper from her title role in the TV show "Rhoda." Six years ago, we came to know her in a new way as she shared what it was like to face terminal brain cancer. There is still another role Harper played that deserves a spotlight even though she never did it for the credit.

In the first People magazine article about her 2013 diagnosis, Harper said, “I just got a letter from a friend who’s getting the Congressional (Gold Medal) in April. I hope I’m around then.” She was. That friend was Nobel Peace Prize laureate and Grameen Bank founder Muhammad Yunus and his invitation begins to reveal the impact Harper’s life has had.

Harper has been a long-term supporter of empowering women through microloans for the poor around the world and of other issues benefiting families here and abroad. How long term? At a House Foreign Affairs subcommittee hearing about microloans in 1987, former Congressman Bob Dornan, R-CA, said, “I want to compliment my colleague Mr. Feighan (D-OH) and tell him what unusual lobbying his bill brings about. Sitting at home last week I got a call from a very important television star, Valerie Harper, otherwise known as Rhoda. And she said, ‘I just know you’re on this bill, Bob.’ And I said, ‘Well if I’m not, I’m going to get on it.’”

When Harper called Dornan and other committee members 32 years ago to discuss this little-known legislation, about 1 million of the world’s most impoverished people had access to a microloan. A third of a century later, the count has risen to more than 124 million very poor families.

Harper wrote about the impact her mother’s commitment to service had in her life when she wrote the foreword to my book "Reclaiming Our Democracy: Healing the Break Between People and Government." “During the years I pursued my passion — a career in the performing arts,” Harper wrote, “a little voice inside me asked. ‘But is this of real value? Should I be doing something of more service — like my mom who is a teacher and nurse?’”

Harper answered yes, and began using her celebrity to advance causes she cared about from the Equal Rights Amendment to the Hunger Project to ending homelessness in America. “My celebrity became a tool I used to contribute to my community and my world,” she wrote. “But I must make the choice to do so and find the means….”

“Her generosity toward people is overwhelming,” said her husband, Tony Cacciotti, “she’s always doing for others….”

I saw that generosity when both Harper and Cacciotti jumped into action to support the Candlelight Vigils my organization, the anti-poverty lobby Results, was organizing the week before the 1990 World Summit for Children.

I called Harper to tell her about the upcoming Summit and its intention to reduce the tragedy of 40,000 children dying each day from largely preventable malnutrition and disease. From my simple description came an avalanche of commitment. Over the next two months, she organized two briefings to bring celebrities on board and a slew of national television appearance on behalf of the Summit.

She also organized a full-page ad signed by 140 celebrities that appeared in The New York Times when Presidents Bush and Gorbachev were meeting in the U.S., urging the two leaders to attend the World Summit for Children. Harper was on the phone day and night, talking to celebrities and their assistants about the Summit and the ad. When the fundraising wasn’t going well, she and Tony paid for the Times ad and for reprints in Daily Variety and The Hollywood Reporter_._ Signers included Frank Sinatra, Jackson Browne, Sting and Elizabeth Taylor, who gave her OK from a hospital bed.

The day after the ad appeared, UNICEF Executive Director Jim Grant wrote Harper, Cacciotti, and their daughter Christina: “I returned last night from an encouraging audience with His Holiness the Pope on the future of the world’s children and our joint efforts to make a difference. I returned to discover The New York Times advertisement. Clearly you and your colleagues have made a dramatic difference for the World Summit for Children and for children the world over.”

Twenty-nine years after that Summit, UNICEF reports that child deaths have been cut by more than half; more than 24,000 young lives are saved every day thanks to the programs for which Harper and others advocated. Valerie Harper was no mere spectator to that change; she was one of the best supporting actors you could ask for. She didn’t do it for applause or to get her name in lights, but at the final curtain call in this lifetime, she deserves a standing ovation for the difference she has made for millions of the world’s poorest families.