Ethel Kennedy, who has died aged 96, was one of the most active and best-known American political women of the 20th century. While her husband, Robert F Kennedy, campaigned first for the Senate and then for the presidency, she supported him while also raising their children. The eleventh and last of them, her daughter Rory, was born after Bobby was murdered in 1968. Beginning in the 1970s, Ethel devoted herself to social causes and latterly served as co-chair of the Coalition of Gun Control.

Her life had previously been struck by tragedy, when her parents died in a plane crash in 1955. Her brother-in-law, President John F. Kennedy, was assassinated in 1963. Two of her children died prematurely – David from a drug overdose aged 28 in 1984 and Michael in a skiing accident in 1997 when he was 39. Her husband was shot at the Ambassador hotel in Los Angeles after his victory in the California primaries for the US presidential race.

Supported by a strong Catholic faith, she remained, in the eyes of writer Hays Gorey, “an inveterately cheerful widow,” never allowing gloom to descend on the hectic lifestyle that was always to be found in Hickory Hill, the family home in McLean, Virginia . . The place was littered with footballs and tennis rackets, and no one was allowed to sit around and mope.

Ethel used sports to promote her husband’s legacy and raise money for the wide variety of charities under the umbrella of the Robert Kennedy Foundation, which also administered what is now Robert F Kennedy Human Rights. This led to the creation of a commemorative tennis tournament in Forest Hills, New York, a celebrity event played on the eve of the US Open for several years in the 1970s.

Born in Chicago, Ethel was the sixth of seven children of Ann (née Brannack), a devout Catholic, and George Skakel, who went from an $8-a-week job as a railroad clerk to selling coal and founding a company with the name Great Lakes Coal & Cokes. When Ethel was five, the family moved east, eventually settling in Connecticut, where she attended Greenwich Academy. She befriended Jean Kennedy, Bobby’s sister, while they were both students at Manhattanville College of the Sacred Heart in New York City. Meanwhile, Bobby – who first met Ethel on a ski trip in Quebec in 1945 – was dating Ethel’s sister Patricia. When they separated, Ethel began the partnership that would define her life.

Ethel campaigned for John F Kennedy when he ran for Congress in Massachusetts in 1946. She married his younger brother in 1950 and their first child, Kathleen, was born the following year.

“They had a great relationship, full of banter and repartee,” recalls Donald Dell, a U.S. Davis Cup captain in the 1960s who played tennis with the couple and became a family friend. “Ethel poked Bobby all the time and he gave as good as he got. But he was always very protective of her and she was very loyal to him.”

When JFK ran for Senate in 1952, Bobby managed the campaign. Throughout the rest of the 1950s, Ethel supported Bobby as he climbed the political ladder, and when JFK went to the White House in 1960, Bobby was appointed attorney general.

JFK’s assassination in 1963 abruptly changed Bobby and Ethel’s lives. Bobby continued the Kennedy story by successfully running for Senate in 1964 and then decided to enter the 1968 presidential race himself.

Early in the campaign, in March, came the stunning news that President Lyndon B Johnson had decided not to run for a second term. It immediately made Bobby Kennedy a heavy favorite to win the Democratic nomination and, in many people’s eyes, the presidency. But that dream died after a shooting in the Los Angeles hotel kitchen in June.

Ethel dealt with her grief steadfastly and called on a wide and diverse group of ‘friends’, as she always called them, to boost her charity work. Sidney Poitier, Sammy Davis Jr. and Charlton Heston were among the celebrities who were always available when she called. A friend remembers calling Heston, whom she always called Chuckles, in an attempt to get him to persuade Roy Emerson, the Wimbledon champion, to play in her tournament. “In return, I’ll star in one of your movies,” she joked. “But I don’t want a maid role – I want some love interest!”

There was some speculation about a possible ‘love interest’ between Ethel and singer Andy Williams in the years following her husband’s death. This gossip continued until, citing her Catholic views, she announced that she would never remarry.

Later in life, a new generation was swept up in the Kennedy lifestyle. Taylor Swift, the country music star, was 23 when she spent some time with the then 84-year-old widow at the family compound in Hyannis Port, Massachusetts, in 2012. Swift refused to go swimming because some of her friends hadn’t. brought their swimsuits. “If you’re so thoughtful, you run the risk of becoming boring,” Ethel said. “Go on, get in the water!”

“So I jumped in,” Swift said. “I thought of it as a metaphor for life. You have to jump in; you have to take your chances. Ethel taught me that.”

In May 2014, the Benning Road Bridge, which connects Washington DC to Anacostia, Maryland, was renamed the Ethel Kennedy Bridge in recognition of the decades of work it had done to improve the lives of young people living along the Anacostia River. of the most polluted in America. To kick-start the project in 1992, Ethel waded in to pick old tires and debris from the water.

The Kennedy who has been most in the news lately is her son Robert F Kennedy Jr., who resigned first as a Democrat and then as an independent presidential candidate. Ethel is survived by him, four other sons, Joseph, Christopher, Max and Douglas, and four daughters, Kathleen, Courtney, Kerry and Rory.