Missing Urn

What kind of person would steal an urn and why? Or was the thief not a person at all? That’s the question we ask today on Real Ghost Stories Online.
Here is a preview of the story.
“As I said, we did not move far, so we did not have a lot of boxes, but we did have two small urns for his cats. He had these cats since he was in middle school (he is in his late twenties now) and always kept the urns together on a low bookshelf. When we moved, he set the bookshelf up pretty much the same way in our living room with the urns next to each other. We now have two black cats (one totally black), and I got in the habit of brushing them nightly after a flea issue. I usually talk to them while I do and go on to my cat about how Aunt Misty is used to loving being brushed. Now I am sitting on the floor in front of that bookshelf and happen to look up at the urns missing the cats. The shelf is at eye level, and immediately I notice that an urn is gone. My boyfriend notices at the same time, and we are a little disturbed. I know for a fact that he placed both on that shelf.”