I think I can safely assure you that Philomena's diet is not based on souls. She rather prefers seed, fruit, and grain -- she only looks like a predatory bird.

[To which Philomena nods. She might have ordinarily been inclined to prank the boy a bit, but she's both stuck in Celestia's mane and looking at him through some odd device. That really limits a bird's options, you know?]