FREDERICK, Md. (AP) — A fourth-grader from Frederick gets to shush the first lady in a new public-service announcement promoting Michelle Obama’s national fitness campaign, Let’s Move.

Nine-year-old Alexa Orlando’s mother said Wednesday that Mrs. Obama’s involvement was kept secret from the participating families until the night before the video was shot last month.

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The one-minute spot shows Mrs. Obama watching a tennis match between Alexa and another girl. Alexa shushes the First Lady to make her stop talking during Alexa’s serve.

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Mrs. Obama silently mouths the word, “Sorry.”

Click here to view the ad.

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