Helen Chavez, widow of the civil rights activist and labor leader Cesar Chavez, died Monday at a hospital in Bakersfield, the Cesar Chavez Foundation announced. She was 88.

Helen Chavez “played a vital role helping her husband give birth to what became the first enduring farm workers union in U.S. history,” the foundation said in a statement, referring to the United Farm Workers of America.

At the time of her passing, she was surrounded by her seven surviving children, 31 grandchildren and 16 great-grandchildren, according to the news release.

The cause of death was not given.

Helen Fabel was born on Jan. 21, 1928 in Brawley, a small city in the Imperieal Valley. Her family lived in a converted horse barn outside McFarland before moving Delano.

She met Cesar Chavez in the mid-1940s, and they married in 1948 after he was discharged from the Navy. The couple had eight children: Fernando, Sylvia, Linda, Eloise, Anna, Paul, Elizabeth and Anthony.

In 1962, the Chavez family left East Los Angeles and returned to Delano, where Helen and Cesar began organizing farm workers.

“Quiet and humble but fiercely determined and strong willed, Helen didn’t speak in public or talk with reporters, but she held deep convictions,” the foundation said.

The statement recounted a telling moment in September 1965, when members of Cesar Chavez’s young Latino union were debating whether to join a grape strike initiated by members of a predominantly Filipino union.

According to the news release, “Helen, in her quiet, no-nonsense way, settled the debate by asking, ‘Are we a union or not?'”

Details about memorial services were expected to be announced Tuesday.