How Richard Simmons Boosted Derek Hough’s Confidence on ‘Dancing with the Stars’

Derek Hough is paying tribute to the late Richard Simmons.

The late fitness guru died on Saturday, July 13 — one day after his 76th birthday — his longtime publicist, Tom Estey, confirmed to PEOPLE. Since his death, several fans and friends have expressed their grief, including the Dancing with the Stars judge. 

Hough, 39, posted a heartfelt tribute to Simmons on Monday, July 15, featuring behind-the-scenes footage of Simmons visiting Hough and his dancing partner Jennie Garth, 52. Even though Simmons was visiting the pair to lift Garth’s confidence, he spontaneously serenaded Hough with a silly improvised song about his hair. 

“In 2007 My very 1st season on @dancingwiththestars I had the pleasure of meeting this wild ball of energy,” Hough wrote on Instagram. 

He continued, “Mr. Simmons was there to help @jenniegarth with her confidence but ended up boosting mine instead with a song about my ‘perfect’ hair. Rest In Peace.”

In the video, Simmons is filmed joking with Garth about Hough’s “perfect hair” before he breaks out into an improvised song. “Derek’s got perfect hair,” Simmons sang, before concluding, “And I don’t want you to mess it up!”

Simmons spoke exclusively with PEOPLE in a rare interview two days before his death, revealing how he planned to celebrate his 76th birthday. He wanted to keep things simple, before stating how “grateful” he was to be “alive for another day,” Simmons said.

General Hospital star Lynn Herring also spoke with PEOPLE about her time with the late star when he appeared on the daytime soap in 2013. “Richard Simmons meant a lot to so many folks including me,” Herring, who plays Lucy Coe in the soap opera, said.

“When Richard walked on our General Hospital stage it would sizzle with his life force, his wicked sense of humor, his joy of entertaining and his love for us all,” the actress recalled. “The last day I worked with him I admired his shirt that had a beautiful jeweled bird on it. When I finished my scenes and came back to my dressing room it was sitting on my couch with a simple Love, Richard.” 

“Thank you Richard for all you gave of yourself to so many!” she concluded.  

Diane Sawyer revealed to PEOPLE the last messages she and Simmons exchanged before his death. Shawyer and Simmons previously had “wonderful conversations” and he agreed to an interview with her, Sawyer said.

“I was truly moved by Richard’s complex insight into life and people, including himself — how we rise and how we fall,” Sawyer, 78, told PEOPLE. “I will always think of the room full of flowers he sent me and how each bouquet having the same note: I trust you.”

“Richard’s last text to me was straight from the [Carole King] song ‘You’ve Got a Friend.’ Whenever you want to talk, just call out my name, and I’ll be there,” the ABC News journalist said.

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“The Simmons family is overwhelmed and beyond grateful for the outpouring of love shown to our beloved Dicky,” Estsey shared in a statement with PEOPLE on behalf of Simmons’ family on Tuesday, July 16. “He is up above smiling down at all of you.”