Complex sentence: Singer songwriter Josh Thompson previously with Sony Music Nashville joined the roster in September 2012 by the summer of 2015 Toby Keith and his daughter Krystal Keith became the only artist's signed to the label.
Split into simpler sentences: Singer songwriter Josh Thompson, previously with Sony Music Nashville, joined the roster in September 2012. By the summer of 2015, Toby Keith and his daughter Krystal Keith became the only artist's signed to the label.