Who is making him laugh?

After we had lunch the other day, I sent each of the children to their rest time space. I sat down to have my own quiet time when I kept hearing cackling coming from my bedroom. (Aaron's rest time space) I thought for sure that Martin had come downstairs and they were in their cutting up together. I quietly peaked into the room, and saw that the cackling coming from Aaron was because of a book he was reading.
I ran and grabbed my camera as quickly and quietly as possible ... and shot a quick video of him.
He was reading an Amelia Bedilia book. I love how much he loves to read. I love how much he just seems to "get" things. I LOVE to hear my children laugh!