to view south falls. at the top, they stopped for a cold drink near a double railing. >> i gave him his drink. and i put mine down. and as soon as i was putting it down i heard him say, mommy, look, i'm sitting down. as soon as i turn around he was over and falling. >> it was a one-second thing. we lost sight of him and we saw him fall down. >> so, i just started screaming. i didn't know what to do. i was just screaming like crazy. >> reporter: the boy's father did. he didn't hesitate to jump over the railing. >> i don't know where i was going to land. just instinct. >> reporter: a witness snapped this picture. ramiro slid 70 feet until he reached his son. they stopped and he just held on, hoping to avoid the base of the 177-foot falls. >> i feared he was going to go all the way down to the rocks. >> reporter: good samaritans already at the bottom helped them down safely.