Just found this video on youtube... At first it looks like the peacock really is attacking the boy, but that is not exactly what happened...
After reading the comments, one of the kids replied from the video saying that what you couldn't see was a lady to the right (out of frame) yank a train feather out for her son. I could not agree more with another comment saying how would the lady like it if someone came up and pulled out some of her hair.
I really HATE it when kids, and especially adults, try to pull out feathers off of zoo peacocks. I feel soo sorry for the bird, and the kids could have gotten hurt because of the lady. I completely understand why some zoo peacocks seem to stay up in the trees all the time. They probably are avoiding people who want to pull their feathers!