Who is a "Ghost Boy" and why does Sarah and Jerome can see him?

A.Scrooge does not know what the future holds for him.  

Explanation:

he is scared

his humanity shines from every page as he bears witness to the tragedy which befell the jewish race at the hands of the nazis. wiesel was a romanian-born jew whose home town of sighet was occupied by the hungarians for most of the second world war. in may 1944, all the jews in the area were forced into cattle wagons and transported to auschwitz.

the anwser is went creeping down the river again, across the wide lonely marshes to the sea.

i longed to go with them out into the world to seek my fortune in foreign lands—africa, india, china and peru!

and, dreaming of the lands i had never seen, i'd sit on there, watching till they were out of sight.