I don't own Supernatural
Castiel's POV
I find these humans strange. This child pretended to fall asleep then as the woman left the room, the child sat up in her bed. I think I will make my presence known. I fly to her window, and I knock on the window. A minute later, a little head appeared on the other side of the glass. She stared at me. Then she waved. I waved back. She opens her window a little and says, "Who are you?"
"I'm Castiel. I am your guardian angel."
"What's an guardian angel?"
"I am sent by the Lord to watch over you. You see me because you are special. I want you to keep this a secret that you saw me because not everyone sees their guardian angel. It wouldn't be fair for them. You know what I mean."
"Yeah" She yawned.
"I can see your tired, I will always watch over you. I will be back soon."
"Okay."