Lisa Rinna mourns ‘Days of Our Lives’ co-star Patrick Muldoon’s death decades after their fling

Lisa Rinna posted a tribute to her former “Days of Our Lives” co-star Patrick Muldoon on Monday, decades after their fling.

The “Real Housewives of Beverly Hills” alum shared a throwback snap of herself and the late actor smiling in a ’90s promo for the soap opera via Instagram Stories.

She captioned the social media upload with a heartbreak emoji.

Rinna, 62, and Muldoon, who suffered a fatal heart attack over the weekend, respectively played siblings Billie Reed and Austin Reed onscreen.

In 2021, the Bravolebrity opened up to People about her “surreal” short-lived romance with her fellow cast member.

“[I had] an affair with the guy who played my brother,” Rinna told the outlet at the time — before clarifying the dalliance consisted of “a couple of one-night stands.”

The actress added, “Patrick Muldoon and I had, like, a thing.”

The duo filmed the series together between 1992 and 1995, both going on to reprise their roles in later years — and joining the “Melrose Place” cast.

News of Muldoon’s shocking death at age 57 broke on Monday.

The Sleeping Masses singer was pronounced dead at his and partner Miriam Rothbart’s Beverly Hills, California, home on Sunday.

Rothbart found her partner unconscious on the bathroom floor after the couple spent the morning together.

Muldoon looked happy and healthy during his last public appearance at the 53rd Annual Saturn Awards in March.

He last posted to Instagram on Friday to share his “excite[ment]” over an upcoming project “Kockroach.”

This is a developing story…