Hugh Hefner’s longtime secretary Mary O’Connor died at the age of 86 on Sunday, Jan. 27. 

Hefner broke the devastating news Sunday night on Twitter, writing, “Mary passed away today. We loved her more than words can say." Her cause of death has yet to be revealed.

O'Connor was a mainstay in the Playboy mansion and made several appearances on Hefner's E! reality show "Girls Next Door." If any girl wanted to be a Bunny, they had to go through her first. 

The show centered around Hefner’s bachelor lifestyle in which he lived with his three girlfriends--Kendra Wilkinson-Baskett, Bridget Marquardt and ex-fiance Holly Madison. O’Connor was shown offering the girls advice, assisting with the Playboy business and helping out around the ranch.

Marquardt acknowledged O’Connor’s passing and thanked her fans for their support.

“Thank you for all the sweet messages, Mary O’Connor will be missed,” she tweeted.

Wilkinson Baskett, who is a mother to Hank Jr. and wife of former NFL star Hank Baskett, also reflected on her time spent with O’Connor.

“RIP Mary O’Connor. She was an amazing person who helped me through so much. But I know she’s happy with her boo Captain Bob,” she tweeted.

For over 40 years, O’Connor provided a strong support system for Hefner and she stayed with him through all three marriages. Hefner’s new wife, Crystal Harris, also tweeted condolences saying, “It’s a very sad day at the Playboy mansion. We love you Mary.”

On New Year’s Eve, Hefner, 86, tied the knot with 26-year-old Harris. The nuptials were originally planned to take place in June 2011 but Harris called the wedding off five days before the wedding. Hefner divorced his second wife Kimberly Conrad in 2010 and his first marriage with Mildred Williams ended in divorce in 1959. Hefner has two children.