There was noise coming from the birdroom a few minutes ago - the distinct sound of Petey repetitively raising the tray on top of his cage and it falling back down. As I commented on it, the Boy got up and said 'oh, I should check that out, that's the Petey alarm'.
And as it turns out, Petey was reporting something. The Boy hadn't closed Pixel's cage properly and she had gotten out. I much prefer Petey "tattling" on her than there being an accident.