Translation:Why are you throwing a stone at my cat?
They do have the Kattenstoet in Ieper. They only throw stuffed animals now though, so no worries. https://www.amusingplanet.com/2017/07/kattenstoet-cat-throwing-festival.html
So, a little discrepency in language. The literal sentence is "to my cat" which in English (USA, CO) has a intention of the cat catching the stone. "I threw a ball to your kid" and "I threw a ball at your kid" have very different meanings where I come from.
Is there a similar situation in Dutch? Maybe using naartoe?