KISS frontman Gene Simmons announced in a heartbreaking social media post Thursday night that his mother, Flora Klein, has died. She was 93.
He shared the news alongside a throwback photo of himself as a child next to Klein.
"I lost my mother. My mentor. My moral compass. And I am heartbroken," he wrote. "My Mother, Flora Klein, passed away at 93 years of age. No illness. No pain. She simply quietly, went to sleep."
"My Mother will always be in my thoughts and in my heart. Today. And Forever. And I would urge all of you to run over, put your arms around your mother, kiss her and tell her how much you love her. Do this every day!"
Many of the rocker's Instagram followers left their condolences in the comments section of the post.
"Sorry for your loss," one Instagram user wrote.
"I am so sorry for your loss. She will always be in your heart," another said.
Hours before announcing her passing, Simmons shared a gallery of photos of himself with his mother throughout the years. "The best mother in the world," he captioned the post.
Simmons' son, Nick Simmons, paid tribute to his grandmother via social media as well, sharing a throwback, image of him as a young toddler with her. "Flora," he simply captioned the post.
Flora. pic.twitter.com/DK7ZQcNBX8— Nick T. Simmons (@nicktsimmons) December 6, 2018
Simmons' wife, Shannon Tweed, also shared the news on Facebook, sharing an image of Simmons and his mother. "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."
Simmons gushed over his mother's strength earlier this year when opening up about the fact that Klein was interned at a Nazi concentration camp during World War II and was one of only two family members to survive, along with her brother Larry.
"She saw her mother walk into a gas chamber," Simmons told The Sydney Morning Herald this year. "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."
The Israel-born rocker said that he and Klein immigrated to the United States when he was just eight years old, although his father, Ferenc "Feri" Yehiel Witz, remained in Israel after having left the family two years prior.
"When we arrived in America neither of us could speak a word of English," he said. "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."