See Oscar Winner Matthew McConaughey's Prom Picture

(Photo Credit: Jason Merritt/Getty Images)

When "Dallas Buyers Club" star Matthew McConaughey took home the best actor Oscar at last night's 86 th Academy Awards, it wasn't just Hollywood royalty inside the Dolby Theatre sending him congratulations.

Proving that throwbacks on social media can pop up all the time, McConaughey, 44, got a Twitter shout out from the niece of his high school prom date.

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The woman, Leah Pickett, not only sent the actor a note of "congrats" on Twitter, she also posted a photo of the Texas native in classic '80s prom attire.

The photo has been retweeted more than 7,000 times, which explains why the day after McConaughey won his first Oscar, the most viral photo of him is not the one of him with the golden statue, but of him dressed in a black tux posing in front of white balloons and a moon and stars taped on a wall alongside his date.

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"My aunt's high school prom date just won an Oscar. Congrats, Matthew McConaughey! #oscars ," tweeted Pickett, who did not immediately reply to ABCNews.com's request for comment.

Picket, who says in her Twitter profile she is a contributor to the Chicago Tribune, provided more details in a later tweet, saying the pair's prom took place in Longview, Tex., and that McConaughey's date is her mother's sister.

She also noted that her aunt is "still beautiful, and happily married," as is McConaughey, who has three children with his wife, Camila Alves.

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There was no date on the photo, but it likely took place sometime during the late 1980s.

One detail in the photo could confirm that timing. McConaughey's date is wearing blue heels that perfectly match her dress, a sure sign of '80s fashion.

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