Blue Ivy Carter becomes youngest ever on Billboard (AP)

FILE - In this Jan. 11, 2009 file photo, Beyonce, left, is joined by husband Jay-Z, as she arrives at the 66th Annual Golden Globe Awards in Beverly Hills, Calif. Through a rap verse, Jay-Z has confirmed the birth of 'the most beautiful girl in the world' — his newborn daughter.  The song 'Glory' made its debut on his social website Monday, Jan. 9, 2012, two days after he and Beyonce reportedly gave birth to a daughter, Blue Ivy. (AP Photo/Matt Sayles, file)AP – She’s not even a week old, but Blue Ivy Carter is already making music history.