The two, who have said they are one another's biggest supporters, spent the Christmas holiday together with their families in Las Vegas, and Jamie Lynn was spotted sitting front row at Britney's opening night of her two-year residency, "Piece of Me," at the Planet Hollywood Resort & Casino.
"I'm just there to be a cheerleader and that's kind of intimidating," Jamie Lynn told MTV News about getting onstage with Britney during her performance. "I don't know how to dance."
She may not know how to dance, but Jamie Lynn certainly can sing. Jamie Lynn recently stopped by MTV News to talk all about her new country track, "How Could I Want More," and while she was here, we decided to put her Britney knowledge to the test, having her complete the lyrics to some of her sister's songs.
We started off with two of Britney's most recognizable songs: "...Baby One More Time," and "Oops!... I Did It Again," a song that Jamie Lynn covered at a concert in Nashville last month.
Things got a little more difficult as we challenged her to complete the lyrics of "I'm Not a Girl, Not Yet a Woman" and "If U Seek Amy," but we figured things would be much easier with her own song with Britney, "Chillin' With You," off December's Britney Jean.
So how did Jamie Lynn do? You'll have to watch the video to find out!