KISS rocker Paul Stanley revealed this week that his father, William Eisen, had died at the age of 101.

On Sunday (Nov. 7), the KISS guitarist and co-lead vocalist shared a recent photo of him and his dad that included a touching message announcing the death. The 69-year-old KISS member acknowledged Eisen's advanced age and fondly recalled his father's life.

Stanley said, "My dad William Eisen has left this earth after 101 years & 7 months. His thirst for knowledge never wained. He could speak on virtually any subject. His pride in my accomplishments was heartwarming as was seeing his love of my family. He said he'd always be with me and he will."

In the 2005 biography KISS: Behind the Mask, Stanley remembered of his upbringing in New York City, "My family wasn't that well off. When I was six, my father bought me a bike, which was the only thing that I was given of any value. We weren't affluent, but we survived. There were times when money was very tight. In Manhattan, the four of us lived in a one-bedroom apartment; my parents slept in the living room and my sister and I shared the bedroom." [via Blabbermouth]

Eisen was a Holocaust survivor, and he was born in Poland before he relocated to New York, according to Outsider. Stanley's mother, Eva Eisen, who died in 2012, came from a family that fled to the U.S. via Amsterdam from Nazi Germany.

No further information regarding William's death was shared on Sunday. Naturally, it's presumed that his family and Stanley, who was born Stanley Bert Eisen, would appreciate privacy at this time.

This fall, KISS finished the 2021 U.S. leg of their End of the Road tour, but concerts were affected when Stanley tested positive for COVID-19, as did bandmate Gene Simmons. KISS were due to play a Vegas residency, but it's now reportedly been canceled.

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