Reese Witherspoon is mourning the death of her Penelope costar Catherine O'Hara. "Feeling so sad about the passing of Catherine O'Hara," Witherspoon, 49, wrote via her Instagram Stories on Saturday, January 31. "Catherine was such an inspiration to me. I worked with her on a movie called Penelope back in 2006, and her creativity was boundless." Witherspoon continued, "She never ceased to amaze me with her generosity toward her fellow actors and filmmakers. In real life, she was just as warm and delightful as she seems on film - a pure delight.