Fred C. Trump III, the son of Donald Trump’s older brother, recalled his uncle constantly using the n-word in casual conversations during the 1970s. According to Fred’s new book, All in the Family: The Trumps and How We Got This Way, he detailed an incident that allegedly occurred on a seemingly normal afternoon at his grandparents’ house in Queens, N.Y., where his uncle arrived visibly upset. He described how the former president showed him his damaged Cadillac Eldorado convertible: “‘N——,’ I recall him saying disgustedly. ‘Look at what the n—— did.'” Fred knew, even as a kid, “That w…