In the story buried for 60 years, why did children write that Japan defeated China as China defeated Japan?

I think, on the one hand, it highlights the patriotism of children, that is, it teaches us to be patriotic and learn from his spirit. On the surface, it is. The child's spirit is very touching. However, there are many loopholes. The article didn't say whether it was Chinese or Japanese. Second, whether the Japanese army speaks Chinese or Japanese.

However, I don't believe this, because I am making a Chinese paper, and this story is reading.