At the beginning of the game, when you are fleeing Earth, you can see the child you will eventually talk to running away from Husks. Before you get to the part where you see Husks climbing up the wall (the first time you shoot at something), you can see the boy looking below, looking over the railing. When the Husks arrive and Anderson coaxes you to shoot them, continue to observe the boy run into the building and lock the door. The building is blown up seconds later, but he apparently survives in the vent.