Alto’s father, Peter Alto, an architect with Group Mackenzie, recalls his daughter swaying to the radio when she was still in diapers. She had already been singing and taking piano and flute lessons for several years when she first asked her parents if she could go to the rock camp. That’s when Katie, then 11 years old, told her parents that the instrument she really wanted to play was the drums. “I just thought it would be really cool to bang sticks on something and make lots of noise,” she explains with a shrug.

Such examples of classic drummer logic notwithstanding, Rose and Alto are not typical young rockers. They’re not rebelling against the grown-up world—their parents, whom Rose calls “our only groupies,” can be seen running the merch table and bopping their heads in the front row at Blübird shows. Alto is a classic over-achiever who volunteers as an acolyte at her church and belongs to a girls’ soccer league that she has dubbed “Intense Soccer,” while Rose is a shy, soft-spoken teenager who enjoys baking scones and knitting in her spare time. They’re not playing music to be cool or popular: Alto’s parents have even accused her of “leading a double life,” because she prefers to keep her role in Blübird a secret from her friends at school. And Alto herself is quick to say that she and Rose are not “those really angry kind of rockers.”

“We don’t try to act tough, and we hate bands that scream all the time,” Alto says. “We just want to play songs that are meaningful and deep.”

But rock does serve one function for Alto that it has for musicians throughout the years: It gives her an outlet for the painful teenage emotions she might not otherwise know how to articulate.

“Sometimes I see her playing, and she’s biting her lip, and I know it’s a kind of catharsis for her,” Peter says.

That’s always been part of the point of Portland’s Rock ’n’ Roll Camp for Girls. When McElroy, a former roadie, founded the camp in 2000, nothing like it existed. Today similar organizations have sprung up throughout the United States: in New York, San Francisco, Tucson, Nashville and Washington, D.C. This month the camp—and Blübird—will receive even more exposure when a documentary about the rock camp, Girls Rock!, debuts in major cities nationwide. (In Portland the film opens at Cinema 21 on March 7.) And in June, Chronicle Books will release a book about the camp featuring a testimonial written by Alto and Rose.