We're going to turn to prom season in full swing. So many teenage girls using technology to make sure there's no duplication when it comes to the dresses for the biggest of ghts. And abc's diana perez... See More
We're going to turn to prom season in full swing. So many teenage girls using technology to make sure there's no duplication when it comes to the dresses for the biggest of ghts. And abc's diana perez has that story. Oh, my god. Reporter: It's the scenario that's caused friendships like those on "beverly hills 90210" to crumble. You said you weren't going to buy it. Reporter: Showing up to the prom in the same dress that someone else is wearing, is the ultimate teenage nightmare. Just ask these teens. In high school, people will definitely notice that someone's wearing the same dress. If we're spending $400 on a dress, I'm sure none of us really want to be in the same one. Reporter: To prevent duplicate dresses, the girls are among a growing number of teens to turn to social media. The minute a girl picks a dress these days, that dress is immediately either posted on facebook or twitter. And the girls are saying, this is my dress. You can't buy it. It's mine. Reporter: Anne hathaway likely wishes she had used social media to call dibs on her oscar gown. She reportedly wore this second-choice drs, learning that there was a dress similar to her first choice. Celebrities shutter for being mistaken for a twin on the red carpet. While the girls say their prom gown pages are supported. People leave nice comments. Like, that's a pretty dress. Reporter: Other girls from other schools from been driven to tears by negative comments or too few people liking their dresses. Sometimes, they'll say, how much do you like my dress? And that can end up being really troublesome because people can say mean things. It reese pretty. Reporter: Thels stand by their facebook page, which allowed them to call dibs on their dresses months in as vance. If anything, creating this facebook page is a new element of anticipation I don't think was there before. Reporter: For "good morning america," diana perez, abc news, new york. Here's to prom.
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