Gave it a listen, Beat LA. She's generic and boring. Mildly talented, but I've seen thousands of girls just like that over the past decade. She probably wouldn't stand out enough to make it onto American Idol or X-Factor. It's a rough business with thousands of mildly talented folks trying to break into it.
Her musical talent isn't going to carry her. She would need to reinvent herself as some ridiculous character with absurd costumes, outrageous hair, and probably a controversial song/video about sex and/or drugs to be relevant in the industry. But I mean, it's not like Lady Gaga or Ke$ha were any more talented... they just got connected with the right people who gave them a new image.
Miley Cyrus had the disney machine pushing her for years and even after having built a known-brand with a reasonably large fan-base, they determined she couldn't succeed in the Taylor Swift pop-country bucket and rebranded her last January as a new-age Madonna. It's tough.
Apologize in advance if that's your sister.