The poignant poem that Rob reads at the end, supposedly written by the character Joe Coogan, was -- like the script -- actually written by Carl Reiner.
The sonnet (refernced elsewhere in Trivia as written by Carl Reiner) reads:
My eyes will never behold which my heart doth see so clearly
Inward stirs this passion: deep, beknighting, leading my path away from all and to my love.
I reach out for thee and pray your hand be there to welcome mine
Your light alone, where my life be spent, where my soul must soar
As revealed in a 1960 episode of the This is Your Life program, there was a real Joe Coogan. He was not a priest. He was a Corporal in the U.S. Army in the entertainment unit along with Reiner. According to Reiner, he was a good writer but a "rotten" actor. Coogan lived in Philadelphia after service.
The sonnet recited in this episode reads: "Mine eyes will ne'er behold which my heart doth see so clearly. Inward stirs this passion deep, benighting, leading my path away from all and to my love. I reach out for Thee and pray Your hand be there to welcome mine. Your light to illume where my life be spent, for my soul must soar."