Chapter One

Hanji's riding along with the scouting legion when Eren is about five years old and in Titan form, he's small enough at this point that when Hanji goes in for the kill, she finds that inside the lump of flesh that she cut out of the 15 meters' neck, is a child! An unconscious, mostly but not entirely(maybe a missing limb or two, but we know that's not such a big deal to the shifters) unharmed child!
She pulls the rest of the meat off of him, bundles him in her cloak, and carries him off to HQ.

Again, not my story.
It's taken off this thread: snkkink.dreamwidth.org/2124.html?thread=1566284