The mystery hairstylist behind Donald Trump's signature 'do

The secret behind Trump's hair has become a guessing game in tonsorial circles. Does he visit daughter Ivanka's hairdresser Julien Farel or former wife Ivana's longtime colorist Louis Licari? Word in the beauty world is that he saw famed transplant expert Walter Unger a long time ago and has tended to his own wispy locks for years. One of New York's top stylists, who worked on a magazine shoot with the mogul during the Apprentice years, says he approached Trump to adjust his 'do. "He said, 'You can spray but don't touch! The only one I allow to touch my hair is Melania.' ''

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But things might have changed with the presidential hopeful's tresses. Insiders are whispering that Melania visits a discrete boutique salon called L'Appartement, conveniently located across the street from Trump Tower on 57th Street, and that her husband may be quietly using its services, too. Oddly enough, the salon's owner and top hairdresser is a Frenchwoman named Tiffany Kaljic, and anyone who knows anything about Trump is aware that he is a bit obsessed with the name Tiffany. He bought the air rights to the famous jewelry store for $5 million in order to build Trump Tower. He named his youngest daughter Tiffany (his now 22-year-old with second wife Marla Maples). He has admitted to watching the 1961 movie Breakfast at Tiffany's countless times and likes to screen it for people riding on his plane. And the elevator leading to L'Appartement has Trump-worthy gilding, while its walls display blown-up stills of Audrey Hepburn from the film.

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When reached at the salon and asked about the Trumps, Kaljic was taken aback. "These people are my clients,'' she said. "I have to respect their confidentiality. If they want to discuss it, they can, but I cannot.''