How does this whole guardian angel business work? Am I the...

How does this whole guardian angel business work? Am I the only person who can see you? I mean, are you invisible to everyone else?" Patch stared at me like he hoped I wasn't serious. "You're not invisible?" I squeaked. "You have to get out of here!" I made a movement to push Patch off the bed but was cut short by a searing jab in my ribs. "She'll kill me if she finds you in here. Can you climb trees? Tell me you can climb a tree!" Patch grinned. "I can fly." Oh. Right. Well, okay.