Miley Cyrus "definitely" a good role model

Miley Cyrus is "definitely" a good role model, says her Hannah Montana costar Shanica Knowles.

"I'm going to give her props for that. She's doing an amazing job and I’m not really surprised by her success because she definitely deserves it," Knowles tells American magazine People. "She is, and she always has been [a good role model]."

17-year-old Knowles - who plays Amber Addison in the Hannah Montana series and movie, adds: "She's really talented, and she's really spiritual and she has a good heart."

For the girls, it’s not all work and no play. Shanica reveals that despite their hectic schedules, the two teens make time to pal around off set.

"It’s not a ritual, but ... every Friday we have a live audience show, and me, Miley and Anna Maria will go shopping afterward or just spend the night at [Cyrus'] house, and just do fun girl things. Or she'll invite us to watch movies, eat popcorn, be goofy in our PJs."