Selena Gomez Reliant Stadium March 6, 2011

See photos of the teen pop star in our slideshow.

Teen-pop star Selena Gomez showed off a new, deeper register during her kid-friendly Sunday night set at RodeoHouston. It's easy to forget that these kids can age just like everyone else, even as they make us feel old. Since her rodeo appearance last year with Justin Bieber, she turned 18 and also started dating the current prince of pop.

Her covers-heavy set, including stabs at modern standards by Taylor Swift and Pat Benatar and a song co-written with Katy Perry, showed a woman eager to grab the same rungs as her heroes, even as she is still slowly crawling out of the Disney Music machine.

She brought out her father, Rick Gomez, who looked very youthful for having an 18-year old pop star in his family, for the crowd to sing him "Happy Birthday" midway through the show.

We still wonder if he's shown her daughter's swaggery boyfriend his gun collection. That's probably a good way to stave off the roaming hands of the Canadian heartthrob.

The older that Gomez gets, the more comfortable she looks onstage and engaging in banter with her crowds. Her voice is catching up to her age bracket, as her fanbase seems to grow with her. Her music is still primarily pop-rock, with the occasional techno flurries.

It's generic, but her voice is going to be a shining spot in the coming years if the material gets better.