David Gail's cause of death has been confirmed after the Beverly Hills, 90210 actor died at the age of 58.
News of his death was confirmed by his sister, Katie Colmenares, who'd shared a sweet photo of the two of them together as she shared the sad news.
She wrote: "There’s barely been even a day in my life when you were not with me by my side always my wingman always my best friend ready to face anything and anyone w me.
"The bears will never be the same but I will hold you so tight every day in my heart you gorgeous loving amazing fierce human being missing you every second of every day forever there will never be another."
The actor's cause of death has now been revealed to be complications from a sudden cardiac arrest, a representative for the family told E! News.
The outlet reports that Gail was found unresponsive by emergency personnel, and was given CPR and defibrillation in an attempt to save his life.
The actor was placed on life support where he remained for several days before he was pronounced dead on January 16.
The representative added: "The family has no reason to suspect the cause of his death was anything but heart failure.
"David will be remembered for his love of acting and his absolute passion and dedication to his friends and family. He possessed a unique quality that made everyone feel special in his presence."
Gail's mom Mary said in a separate statement: "We are extremely touched by the outpouring of love from David's dedicated fans and colleagues. We are grateful for all the support received during this very difficult time."
Gail had been best known for starring as Stuart Carson on Beverly Hills, 90210, as the fiancé of Shannen Doherty's character Brenda Walsh.
Doherty had shared a tribute to Gail on her Instagram story following the news of his death, as she posted a throwback photo of the two of them on the show together.
As well as his time on Beverly Hills, 90210, Gail was also known for his role as Dr Joe Scanlon in Port Charles, a spin-off of General Hospital.
His Port Charles co-star Jon Lindstrom had shared his sadness at news of his friend's passing, writing on X (formerly known as Twitter): "So saddened to learn of the passing of my former cast mate David Gail.
"He was a good guy, a pleasure to be around, and I always thought he was a real talent. Sincere condolences to all his loved ones. Rest in Peace. Flight of Angels."
General Hospital star Kin Shriner added: "RIP to my old pal David Gail, He was fun to be around, we went to the Bahamas diving, he was a good guy!"