Apple and Rovio review: The app store and angry birds 2

I have been charged thousands of dollars from the App Store for I’m game purchases made by my kid. It’s unbelievable how he was able to do this in just a few weeks. It’s so much like gambling for him. The game where you try to reach the top of the tower and it cost more and more. He said he just wanted to reach the top so bad. Please help me recover my money. We struggle financially as it is. I don’t know what to do.