By Tim McKeough Alice Mason was New York City’s broker to the elite and a master at the art of hosting. One fête would alter her legacy and strain her relationship with her daughter.

At Mar-a-Lago, ‘Uncle’ Elon Musk Puts His Imprint on the Trump Transition He’s on the patio. He’s on the golf course. Everywhere President-elect Trump looks, there is the world’s richest ...