I lived in Mexico for more than half my life, so I know the Mexican urban legends better than anyone.
When I was 12, I was with my brother walking through a forest. We were getting really tired and it was getting really dark, so we decided to walk back home. On the way there, we heard a woman crying. When I heard what she was screaming my stomach sank. She was screaming, "Mis hijos mis hijos! Donde estas mis hijos!!"
My brother and I looked at each other for ten seconds and booked it. We ran faster than we ever had. But the shrieking kept coming closer, until I heard it in my ear. All I really remember after that is someone grabbing my ankle, tripping me. The next morning, I woke up in the hospital because when I tripped, I hit my head on a rock. I told my mom the story, but she didn't believe me.
She said, "You just hit your head and thought those things happened."
But I know it did happen, because I still have the scar.