The incomparable Buddy Holly was born September 7, 1936 in Lubbock, Texas.  During his short career, Holly had a string of hits including "That'll Be The Day" and "Peggy Sue".
In 1991, Brooks and Dunn reached #1 on the country Billboard singles chart for the first time in their career with "Brand New Man".
September 7 is a good day for country babies!  In 2010, Rascal Flatts' Joe Don Rooney and his wife Tiffany had a daughter, Raquel Blue Rooney.  And in 2014, Lady  Antebellum's Dave Haywood and his wife Kelli have a son, Cash Van Haywood.