Flóra "Florence" Klein, mother of KISS bassist and singer Gene Simmons, has passed away at the age of 92.

Simmons' wife, Shannon Tweed Simmons, reported the news on Facebook, posting an image of Simmons and his mother, expressing, "Rest in peace my dear Flora. The best grandma and mother-in-law I could ask for. You were loved and you will be missed."

Klein, a Hungarian Jew, was interned at a Nazi concentration camp during World War II and was only one of two family members to survive, her brother Larry being the other. "She saw her mother walk into a gas chamber," Simmons told The Sydney Morning Herald earlier this year, adding, "Despite the tragedy, she is a positive person who sees the goodness in people's hearts. I wouldn't be that forgiving if I had lived her life."

Uprooting from Israel, Klein and Simmons  immigrated to the United States when he was just eight-years-old, though his father, Ferenc "Feri" Yehiel Witz, remained in Israel and had abandoned the family two years earlier. "When we arrived in America neither of us could speak a word of English," said Simmons in the same report. "My mother worked in a factory that was like a sweatshop – six days a week, no lunch breaks and there was no minimum wage. She was a button and buttonhole worker, handling 1000 coats a day. She made half a penny for every button sewed," he said of her work ethic.

Our thoughts our with Gene Simmons and his family during this difficult time.

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