Patinkin – who starred in Reiner's 1987 classic "The Princess Bride" – mourned his director and friend Rob Reiner on Monday.

Stars of "The Princess Bride" and "Stand by Me" reacted to director Rob Reiner’s death, sharing what he meant to them.

Cary Elwes mourned his former "The Princess Bride" director Rob Reiner on Monday morning in a short and sweet Instagram post ...