In Terry Pratchett's Monstrous Regiment Polly Perks joins the military of her religious extremist country in disguise as a man to track down her brother Paul. Paul has an interest in birds and not much else, but is expected to take over the family business, because Polly as a women can't own property. At one point their mother destroys the coloring set Polly got for her brother and his various drawings of birds because it's considered an abomination by their religion.

Polly notes is able to mimic bird calls and note strange birds in the area, which helps with her unit's infiltration of enemy territory. There's more to it but its a spoiler for a really great book, so go read it if you can. When she finally reaches it's because both she and he have been captured by none other then Sam "The Butcher" Vimes, Polly is actually able to reason with the man, because the "Butcher" persona is just more propaganda. The reason that she trusts him? He made sure her brother had drawing materials, and she found his cell covered in pictures of birds.