SOLVED. YA realistic fiction book read around 2005-2010. A girl tries to hide that her father is a popular musician from her new classmates. [s]

[Eldritch]

A teen girl is the new kid at her high school and doesn't want people to know that her father is part of a famous band. She gets two new friends pretty quickly, a boy and a girl (as is required of all friendship trios in these types of stories). The female friend is gay and closeted. She is initially spotted by the main character because she's carrying a guitar. The main character worries that she has blown her cover when the other girl is taken aback by her referring to the guitar being carried in a "gig bag," rather than a "guitar case."

As I remember it, the book follows the standard story beats of the main character's secret being leaked, but all is well in the end.

[Becca]

Backstage Pass by Gaby Triana. I read the first few pages on Google Books and it includes the 'gig bag' thing you describe.

[Eldritch]

That's the one! Gosh, it's gratifying when that one detail helps. Thank you so much.