I recently penned “the Daddy Diaries” about the joys and horrors of sex in one’s golden years. But here come The Great Granddaddy Diaries! Bob Morris, a witty friend of mine, not to mention a New York Times “Style” section regular, has written a book called Assisted Loving: True Tales of Double Dating With My Dad, chronicling the way his 80-year-old father leaned on Bob to help find himself a new hottie. (“Am I pimping for my father?” sonny boy began to wonder in between hookups.) But pops certainly paid back. As the book notes, he encouraged Bob to find a love of his own, and he did—with ANOTHER witty friend of mine, Ira Silverberg. (My black book is absolutely filled with available, successful gay men, all of whom seem to find each other. I’m so thrilled.) Anyway, if this story isn’t turned into a smash off-Broadway musical, then God is a Nazi.