Jamie Lynn Spears looks so much like her older sis Britney, but we LOVE that Jamie actually sings live!

The 21-year-old mama of one performed "I Look Up to You" at the 3rd and Lindsley Bar & Grill in Nashville, Tennessee.

Before belting it out in the mic, Spears told the crowd, "You can imagine who I wrote it about."

Watch out Carrie Underwood ... sounds like you've got some country competition!