What have you ever done that you really felt guilty about?

When I was nine, My sister had a pet cat named Doodle. She called it Doodle because of its color and her love for Cheese Doodles. However, she decided to hide my PS2 controllers from me and wouldn't tell me where she put them. So I threatened to throw her cat out of the window at the top floor of the apartment complex. She still decided to keep hiding the controllers from me. Therefore resulting in myself picking up her cat and holding it over the edge. She begin to yell at me, and I told her to go get my controllers. Before she could even go to get the controllers the cat began to go crazy and attacked me. My hand released due to the sudden shock. Sending the cat down twenty feet to its crushing death.

She still brings it up to this day, and I am 19.