LAS VEGAS, NV - MAY 19: (EXCLUSIVE COVERAGE) (L-R) Singers Celine Dion and Madonna attend the 2013 Billboard Music Awards at the MGM Grand Garden Arena on May 19, 2013 in Las Vegas, Nevada. (Photo by Kevin Mazur/WireImage)
LAS VEGAS, NV - MAY 19: (EXCLUSIVE COVERAGE) (L-R) Singers Celine Dion and Madonna attend the 2013 Billboard Music Awards at the MGM Grand Garden Arena on May 19, 2013 in Las Vegas, Nevada. (Photo by Kevin Mazur/WireImage)