Cliff Robertson, the actor who portrayed John F. Kennedy in 1963 film “PT-109”, died on Saturday afternoon in Stony Brook, a day after his 88th birthday according to his secretary of 53 years, Evelyn Christel.

Cliff Robertson was said to have died of natural causes.

Cliff Robertson, by the way, has won an Oscar in 1968 for the film “Charly” for portraying a mentally disabled man. His last films included Uncle Ben in the “Spider-Man” starring Tobey Maguire movies.

He also gained attention for his second marriage to actress and heiress Dina Merrill, daughter of financier E.F. Hutton and Marjorie Merriweather Post, heiress to the Post cereal fortune and one of the world’s richest women.

Cliff Robertson’s other memorable projects include the TV programs “Days of Wine and Roses” and “The Hustler,” and the Tennessee Williams’ play “Orpheus Descending.”