Weird things your cat does?

My sister's cat likes to steal small objects. She used to get the kids in trouble before we realized it was her. She would get into their room and steal these little plastic cupcake things from a Barbie set and leave them throughout the house. They hurt like crazy (think: the size of a marble) when you stepped on them and so the kids were supposed to keep them put away. Then time and time again, they'd be out and they'd get in trouble.

Then one night, we saw the cat carrying one around and discovered it had been her all along.