On Friday, Rinna, 57, shared an appreciation post on Instagram for the Clash of the Titans star, 68, in which she poked fun at rumors that he is "having a lot of affairs."
"#Fbf Appreciation Post to my very busy Husband who apparently doesn't live with us, is having a lot of affairs, and is gay," Rinna wrote alongside Hamlin's Sexiest Man Alive (1987) PEOPLE cover.
"Go Harry F------ Hamlin," Rinna added.
Rinna's post comes after a Twitter user alleged that Hamlin had an affair during the summer of 2018.
"My girlfriend f----- Harry Hamlin in muskoka for an entire summer in 2018 — you wanna talk about that @LisaRinna??? Or do you want to talk about his affair with Patricia? #RHOBH," the account holder tweeted after part three of The Real Housewives of Beverly Hills season 10 reunion aired on Wednesday.
Rinna responded to the allegation in an exchange captured by Comments by Bravo, saying: "Yeah and I watched it was hot as hell [fire emoji] Patricia well she's kind of downer I didn't like her so much."
Though the user did not further reveal the identity of "Patricia," another account holder joked about Southern Charm's Patricia Altschul: "If Patricia was Patricia Altschul from Southern Charm, I would watch every second of that."
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"Yep... it was me!!" Altschul replied, as captured by Comments by Bravo.
Rinna and Hamlin tied the knot in 1997 and share daughters Amelia Gray Hamlin, 19, and Delilah Belle Hamlin, 22. Hamlin is also dad to son Dimitri Hamlin, 40, with ex Ursula Andress.
In December 2019, Hamlin opened up about meeting Rinna when the RHOBH star was working at a store selling sunglasses more than 20 years ago.
“We met in a restaurant. She was working at an eyeglass store doing the night shift selling sunglasses. And I happened to know the owner of the store, I was having dinner with him and she came in to deliver the keys when she closed the store at 10. That’s how I met her,” Hamlin explained to SiriusXM’s Jess Cagle and Julia Cunningham on The Jess Cagle Show.
While Rinna has become widely recognized in the time since, most recently with Bravo audiences, Hamlin noted that their introduction came “before she was acting a lot and before she had sort of broken out.”
The Mad Men actor was immediately smitten.
“It was sparks right away,” he admitted, before recalling the humorous conversation the pair shared upon meeting.
“She had just been to the circus the day before and she said, ‘Oh my God, I went to the circus last night and it was so sexy!’ I’m thinking to myself, ‘Wait a minute, here’s this girl. She’s sitting there and the elephants, right, and the clowns and all that.’ Because the only circus I’d ever been to was Ringling Brothers. But she was talking about Cirque du Soleil, which is very sexy, but I didn’t know that. I had not seen Cirque du Soleil at that point, so I thought, ‘If this girl can be turned on by elephant dung and whatever, I’m good with her,' ” he said.