“So sad but forever grateful for all the wonderful memories and amazing experiences #RIPHef #Playboy,” the former Girls Next Door star, 44, shared on Twitter and Instagram along with a broken heart emoji as well as a photo of her and Hefner.
Hefner peacefully passed away on Wednesday from natural causes at his home, The Playboy Mansion, surrounded by loved ones, according to a statement from the Playboy founder’s rep. He was 91.
In October 2002, Marquardt moved into The Playboy Mansion at age 29 and was featured on the E! reality show with Holly Madison and Kendra Wilkinson from 2005 to 2010. The six-season series documented the lives of the Playmates and their relationship with Hefner inside the mansion.
The three ladies also posed together for three Playboy cover pictorials: the November 2005, September 2006 and March 2008 issues.
In July, Marquardt revealed that she hadn’t seen Hefner for a few years.
“I was still going back to some of the parties. Occasionally, my boyfriend [Nick Carpenter] I would go back,” she said on Australia’s The Morning Show. “I was still in touch with Hef—and then we kind of lost contact.”
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Marquardt’s tribute was made public shortly after Wilkinson released her statement to PEOPLE.
“Hef changed my life. He made me the person I am today. I couldn’t be more thankful for our friendship and our time together. I will miss him so much but he will be in my heart forever,” Wilkinson said.