It doesn't matter who they are, or where, or when. Just that there are two and that they stand, side by side, holding hands.
Each holding onto the other's hand, as if it were some sort of shield against the horrors they are experiencing.
There is indeed something that links us all together, a togetherness in the face of adversity. Alone things are hard, but together they are never quite so terrible.
Sometimes we can't survive something without that other person, standing there with us.