The straight line distance from Khan Younis to the border east of the airport is about 12 to 13km. Either you are mistaken or you are making mischief. As for the poor child what parent in their right mind lets their teenage boy go off to the border on Land Day only days after another violent attempt to abduct IDF soldiers has failed, with loss of life on both sides?
Alleged Jerusalem gay pride parade stabber's remand extended by 12 days (Haaretz)
from the article: IDF denies killing Palestinian teen on Gaza border