This question will resolve Yes if the soldier(s) who killed the younger of these two children is found guilty of murder or any other crime related to that killing. This market covers only military or civilian trials by the state of Israel, and will resolve No three months after the first such trial if there is no serious indication that there will be a second.

As I am not well-versed in Israeli law, I am happy to note important information in the comments. There seems to be precedent in both directions for this sort of act in the past, but legal absolution (and no actual charge for the killing itself) appears more common: https://www.theguardian.com/world/2005/nov/16/israel2