Melania locked in standoff with smitten Trump aide who 'supersedes' her: biographer

Melania Trump is locked in a behind-the-scenes standoff with 35-year-old White House aide Natalie Harp over access to the president, according to Donald Trump biographer Michael Wolff. Harp has become a near-constant fixture at Trump's side, which Wolff says has effectively pushed the first lady…