NEW YORK, NY - DECEMBER 17: (EXCLUSIVE COVERAGE) Model Christie Brinkley backstage at the Billy Joel concert at Madison Square Garden on December 17, 2015 in New York City. (Photo by Myrna M. Suarez/Getty Images)
NEW YORK, NY - DECEMBER 17: (EXCLUSIVE COVERAGE) Model Christie Brinkley backstage at the Billy Joel concert at Madison Square Garden on December 17, 2015 in New York City. (Photo by Myrna M. Suarez/Getty Images)