Too Close to the Edge

Artist Penelope had been looking forward to going with her husband, sister and brother-in-law to see the Grand Canyon…even though she was terrified of heights and, when she got there, couldn't bear to get too close to the edge. She watched people balancing on one foot, acting foolish, taking photos, oblivious of the death waiting below them at their feet. Their careless antics made her dizzy, took her breath away. Scared her.
Especially when the woman beside her relates the story of a small child that fell into the Canyon to her death the day before. Many people died that way. Over the edge. Many also died down inside the Canyon. Hikers. Lost people. People on the river going through the rapids.
Then she sees a young girl go over the edge and no one will believe her.
For there was no child that had died–that day anyway. 
Was she seeing things that weren't there…or was there another explanation?