it was peter
No, James Blunt sings in the Credits. If I ever leave this World Alive by FLogging Molly is the last song where Holly sees William again and walks away saying "P.S. Guess what"
In the cave he noticed it when he was invisible
the answer is: apple poop. he sees it in the pool and he starts eating apples and starts pooing out bananas
She sees a replication of a meadow, filled with real trees and flowering plants, and alive with humming birds.
He talks to him