Rat Pack crooner Peter Lawford turned down sex with screen siren Marilyn Monroe because she smelled unpleasant - according to his son.

In a new memoir, CHRISTOPHER LAWFORD KENNEDY reveals his British-born father - who died in 1984 - was a legendary lothario, rivalled pal Frank Sinatra as a womaniser and had the best sex of his life with screen star Lana Turner.

But he refused to get intimate with Monroe.

Lawford Kennedy says, "My dad was real particular (about) hygiene."