Which Princess Bride actor forced director Rob Reiner to leave the set because he’d laugh so hard he’d get nauseous?

The answer is: Billy Crystal. Princess Bride director Rob Reiner was forced to leave his own set during Billy Crystal’s takes because he would laugh uncontrollably to the point of becoming nauseated. Billy Crystal also appeared as a mime in Rob Reiner’s This is Spinal Tap in 1984 and as Harry in Reiner’s romcom classic, When Harry Met Sally. No word on any elements he caused the directors on those films.Source