Sometimes a good idea can turn into a bad idea in a matter of seconds.
This little kid saw his brother chasing a squatty little sheep around and decided "Hey. I'm an assertive guy. I should just climb on top of this sheep that's standing right here. Because I can."
Well, that was a bold move. But when the sheep in question suddenly took off like some sort of woolly comet, the kid was totally NOT prepared, and shrieks in terror.