When Dick Van Dyke first arrived on set of The Dick Van Dyke Show, he felt sure enough about his own talent that he allowed Carl Reiner to coax him into putting his then-unknown name on his new TV show.

With so many veterans of comedy around him, he had a confidence that the show was really coming together, and he was proud to have his name on it.

The only thing he really doubted when shooting the pilot episode "The Sick Boy and the Sitter" was whether or not his new onscreen wife Mary Tyler Moore actually had the ability to do comedy.

"I was concerned that Mary wasn’t much of a comedian," Van Dyke wrote in his memoir My Lucky Life in and Out of Show Business.

"It is hard to imagine," he wrote. "But she was stiff and proper, polite. She didn’t seem to have much of a funny bone. I saw a little Katharine Hepburn in her, but not much Lucille Ball."

While Dick was busy doubting Mary, though, he didn’t notice that he got something pretty major wrong about his own character when he was doing what he considered a perfect reading of the pilot episode: the pronunciation of Rob Petrie’s name.

"As we shot the pilot, I mispronounced Rob and Laura’s last name, saying Pet-re rather than Pee-tree, as Carl had done in the original when he based the name on some actual neighbors of his in New Rochelle," Van Dyke wrote. "Nobody corrected me, and so it stuck."

Just as Van Dyke was wrong about the pronunciation of Rob Petrie’s name, he admitted he was just as wrong about Mary and her comedic talents. He said after a few days of reading together, he knew that Mary really got it when she delivered the line "Oh, Rob!" one day at rehearsal with perfect comedic inflection.

Suddenly, Dick saw what Carl Reiner had seen in the very green Mary Tyler Moore.

"Of course, I was wrong [about Mary]," Van Dyke wrote. "And therein is yet another reason Carl was known as a genius and I was referred to as 'the actor playing Rob Petrie.'"

Van Dyke credited Mary with being an "A-plus student" of the veteran character actors on the show like Morey Amsterdam and Rose Marie.

"She absorbed everything — the chemistry, the rhythm — and emerged a comedian herself," Van Dyke said, adding, "I had never seen a transformation like hers, and I still haven’t."

For Van Dyke, becoming Rob Petrie — however it was pronounced — was a transformation, even if he did pronounce the character’s name wrong, thus changing the way we’ve all referred to the Petrie family forever.

And of course, after The Dick Van Dyke Show ended, Mary Tyler Moore took what she learned onset and transformed again, forever becoming identified as not Laura Pet-re, but Mary Richards through The Mary Tyler Moore Show.

The two costars remained close, but both became slammed with acting work and had to let go, unable to hold onto their time together as the Petries.

"When The Dick Van Dyke Show ended, we vowed to get together for lunch every three weeks," Van Dyke wrote. "It never happened. Busy schedules, career demands, and family obligations made such a well-intentioned promise impossible to fulfill."

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