The 73-year-old had been battling pneumonia, her family said in a statement, according to the Associated Press.
“Sarah was a voice of strength, love and encouragement, and she inspired others, showing that one person could make a difference and change the world – which she did,” the family’s statement said.
The tributes immediately began pouring in.
“All of us at the Brady Campaign and Center to Prevent Gun Violence are heartbroken over the passing of Sarah Brady,” Dan Gross, the group’s president, said in the press release.
“Together with her husband Jim ‘Bear’ Brady, Sarah was the heart and soul of this organization and the successful movement it has become today,” the statement said.
Her husband died last August. He was 73.
James Brady survived a shot in the head after John Hinckley Jr. attempted to kill President Ronald Reagan in 1981. Reagan nearly died from a chest wound.
Nancy Reagan released a statement Friday saying she was “deeply saddened” by the death of her “dear friend” whose friendship was cemented more than 34 years ago.
“We shared an experience that bonded us for life, as we comforted each other in a tiny, windowless office at the George Washington University Emergency Room while awaiting word about whether our husbands would survive the horrific gunshots that had brought them there,” the statement said.
James Brady, who was one of three other people shot by Hinckley, was often in a wheelchair due to partial paralysis from brain damage and suffered slurred speech and short-term memory loss.
Sarah Brady spoke with PEOPLE about other changes in her husband as well.
“He will end his sentences on a higher pitch, generally when he’s laughing,” Sarah told PEOPLE. “Maybe he doesn’t control his laughing quite as well as before the accident. He’ll learn to suppress it.”
The couple became tireless advocates to end gun violence and successfully campaigned to get a law passed that requires background checks for handgun purchases.
She is survived by her and Jim’s son, James “Scott” Brady Jr. and her stepdaughter, Melissa “Missy” Brady Camins.
“I will miss Sarah very much,” Nancy Reagan said in her statement, “but take comfort in knowing that she joined Jim on Good Friday and is now at peace.”
• With additional reporting by LIZ McNEIL