Pranks can be very funny when you get the right people with the right prank.  They're even funnier when you get the same people over and over with the same exact prank.

This guy's sister found a way to get her brother to think she was taking selfies with him when she was actually filming video...every single time.

How does that phrase go?  Fool me once, shame on you.  Fool me twice, shame on me.  Fool me three to ten times and I'm just an idiot.