The intertwining of temporal plans is what gives value to your story.
You have created a mirror game that deceives the reader more than once, until the final horror.
Really well done!
At first, the reader is confused because he thinks that Anton is still a boy (I had almost believed that Anton's grandfather had the same name and was expecting the return of his nephew and his friend Genna), then it looks like an absolutely positive flashback. There is a false supernatural hint (the two pairs of eyes), and then a bad reality that makes us think about the hints of guilt present at the beginning (and gone unnoticed).