Carolyn Goodman, a civil rights activist, whose son, Andrew Goodman, was killed by the Ku Klux Klan, died on Friday of natural causes. She was 91 years old.

Andrew Goodman, along with James Chaney and Michael Schwerner, was shot to death in 1964 while in Mississippi. They were there to help register black voters.

Carolyn Goodman was an assistant clinical professor emeritus of psychiatry at Albert Einstein College of Medicine of Yeshiva University in the Bronx.

According to New York 1, she created a foundation in her son’s memory and at the age of 83 she was arrested in a protest against the police shooting of Amadou Diallo.

Andrew Goodman was only 21 years old when he died. He was a graduate of the Walden School in Manhattan and was a student at Queens College at the time of his death. The Walden School dedicated a building to Goodman in the 1970’s. The building now houses the Trevor Day School.

According to the New York Times’ obituary, Carolyn and her husband received this postcard on the day of Andrew’s death,

“Dear Mom and Dad, have arrived safely in Meridian, Miss. This is a wonderful town, and the weather is fine. I wish you were here. The people in this city are wonderful, and our reception was very good. All my love, Andy.”

She told the New York Times’ in 1965:

“I still feel that I would let Andy go to Mississippi again. Even after this terrible thing happened to Andy, I couldn’t make a turnabout of everything I believe in.”