Video: Christina Hendricks Sings

Christina Hendricks is best known for playing office vixen Joan Holloway in "Mad Men," but when she was 9 years old, the role she wanted more than anything was Ursula in a community theater production of "Bye, Bye Birdie."

"I went in and sang 'You Are My Sunshine,'" Hendricks, 37, recalls in a new interview with Peter Travers. "I was so dismayed I didn't get the part even though I was only 9 years old. They gave it to someone who was, you know, 16."

Still, it was an experience that forever changed her: "I was in the chorus and I was dancing, singing and acting and never stopped!"

For more from Hendricks, including dish about her marriage, what she does for fun-and surprising details about a new member of her family, check back on Friday

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