John Gabriel, 'Ryan's Hope' Star, Dead at 90

John Gabriel, best known for his role on the ABC soap opera Ryan's Hope, has died. He was 90.

The news of his death was announced Sunday on Instagram by his daughter, Andrea Gabriel.

"It is with an unspeakably heavy heart that I share the news of my father's passing," the Lost alum, 42, captioned her post. "John Gabriel was my hero, my role model, and my champion, but above all, my daddy...I will love you forever."

No details were immediately available regarding a cause of death.

Gabriel played Dr. Seneca Beaulac on Ryan's Hope for more than 700 episodes from 1975 to 1989. The role earned him a Daytime Emmy nomination in 1980.

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The actor additionally landed roles in other prominent shows, including Days of Our Lives, Generations, The Mary Tyler Moore Show and Seinfeld, and appeared in films such as The Hiding Place (1975) and The Return of Superfly (1990).

He also played the Professor in the 1963 pilot for Gilligan's Island, which never made it to air. CBS ultimately recast the role, with Russell Johnson replacing Gabriel.

In 1999, Gabriel opened up about losing the part on E! True Hollywood Story's "Gilligan's Island" episode. "It was devastating," he said at the time. "It was the first time in my adult life that I remember weeping."

Gabriel is survived by his wife, Sandy Gabriel, and daughters Andrea and Melissa.