Morrison passed away peacefully in her sleep, according to the Rosie the Riveter Trust organization.
"Even though we were expecting this, it doesn't make it any easier to take," wrote the organization in a statement to ABC7 News.
"Kay embodied the 'We can do it' spirit throughout her life and I don't say this lightly that she will be truly missed. She lit up a room and people were drawn to this wonderful, funny, witty and charming lady. She was a true spitfire! When she visited with you she truly took an interest in you and remembered everything you told her."
Morrison riveted and welded her way through World War II, finding work as a welder at the Kaiser Shipyard #2 in Richmond.
"Did I feel patriotic?" Morrison told ABC7 News in 2017. "I just felt like we had a mission to work hard and bring our boys home. The history came later."
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After being born in Chico on November 23, 1923, Morrison moved to the Bay Area to look for employment to help in the war effort. Morrison and her husband Ray found an apartment on Haight and Fillmore, with Ray unable to serve in the military due to health reasons. Ray was able to find work right away as a carpenter in the Kaiser Shipyard #2, but not so for Kay.
Morrison was discouraged by a posted sign that said "No Women or Blacks Wanted", according to the Rosie the Riveter Trust. But by 1943, Morrison would pass the Navy Welding test with flying colors and became a certified Journeyman Welder, taking the ferry from the Ferry Building from San Francisco to Richmond. From then on, she would work the graveyard shift with her husband, six days a week, until 1945 when the war ended.
"You must be awfully good because it took me three tries before I passed (the welding test)," said a fellow male coworker, according to the Rosie the Riveter Trust. Her wages went from $0.90 an hour, to $1.38 an hour (approximately $20.00 an hour in 2021 dollars).
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In the years following the war, Morrison and her husband would have two children, six grandchildren and numerous great-grandchildren. Ray eventually got into the laundry business, while Morrison worked for Bank of America for over 30 years, retiring in 1984 as a bank branch manager. Kay and Ray were married for 64 years until his passing in 2004.
"Kay looked fondly on her days as a Rosie, and felt privileged to have been given the opportunity to promote women and share her stories with visitors at the Rosie the Riveter WWII Home Front National Park." said the Rosie the Riveter Trust.
The family of "Rosie" Kay Morrison has extended an open invitation for her memorial service on Thursday, at 1:00 p.m. at McCune's Garden Chapel in Vacaville.