In a touching tribute to her older sister Britney, Jamie Lynn Spears dedicated a song called "I Look Up To You" during a performance in Nashville on Thursday. Jamie Lynn, 21, made reference to Britney's lost innocence in the lyrics, singing, "Scared little girl living in a big old world. You've outgrown your room, it all happened way too soon. They took away your innocence. We forgot our strong defense." The siblings have gone through a lot together following Britney's public meltdown and Jamie Lynn's baby announcement at the age of 17. What do you think of her voice? I didn't know she could sing!