Annie Glenn had rarely been seen in public since the senator died.
She died early Tuesday at a nursing home near her family in St. Paul, Minnesota, the AP reported.
Annie Glenn had moved to be near her daughter Lyn, according to the AP.
While her husband had been in the spotlight when he became the first American to orbit Earth, she stayed away from the cameras because she had a severe stutter, the AP reported.
She was able to overcome her speaking challenges after going through a program at the Communications Research Institute at Hollins College in 1973. She was able to speak in public and spoke about her fears when her husband returned to space when he was 77 years old onboard the space shuttle Discovery.
“John had announced one year before that he was going to retire as a senator, so I was looking forward to having him as my own because I had given him to our government for 55 years,” she said at the time.
She was also an advocate for those with communication disorders, serving on advisory boards for various child abuse, speech and hearing organizations. She also started the Annie Glenn Award to honor those who persevere despite a communication disorder, the AP reported.