Shot from the Monitor. I Am Going to Meet My Brother

The heroes of the wonderful Soviet and Russian writer Vladislav Krapivin are always children. Special ones, capable of traveling between worlds, and ordinary ones – if a child can ever be considered "ordinary"...
"Shot from the Monitor" is the first of... five main works in the cycle "In the Depths of the Great Crystal," the events of which take place in neighboring worlds of a unified multiverse. Long ago, Galien Tukk saved his hometown from an attack by a heavy battleship – a monitor, and now, in our time, the story of another boy mysteriously overlays this plot.
The short tale "I Am Going to Meet My Brother" tells about Earth in the twenty-fourth century. The boy Naal is waiting for the return of a photonic starship sent to colonize a distant planet: it turns out that the captain of the ship, who left Earth three hundred years ago, is his only relative.