As the DNC conducted its alphabetical roll call to tally each state’s votes, something odd happened when it arrived at Vermont: The Green Mountain state and home of Senator Sanders skipped its turn. “Vermont passes,” a young woman told the DNC, before shrugging and stepping away from the mic. But what at first seemed like another act of defiance by Sanders loyalists refusing to support Clinton was all part of a bigger plan—and involved an unusual delegate.

The woman at the mic was Aster O’Leary, who was elected as a Vermont delegate to the DNC, representing Sanders, this spring while she was still in high school. O’Leary covered the expenses of attending the convention by raising $2,000 via the for-profit crowdfunding site GoFundMe. GoFundMe, a for-profit company, is a popular fundraising vehicle for non-profits, and dozens of delegates from each major party have used it this year to defray their costs.

Still, few of those delegates got a moment in the spotlight like O’Leary’s. At 18, O’Leary is one of the youngest DNC delegates. Party members initially instructed her to read off part of Vermont’s votes during the roll call, but they changed their minds at the last minute, telling her to pass instead. Because of that maneuver, the DNC was forced to come back to Vermont at the end of the roll call, setting the stage for Sanders to symbolically move to nominate Clinton by acclamation—much the way Clinton herself did for Barack Obama in 2008.

O’Leary says the sequence of events was particularly painful for the Vermont delegates—all but four of whom, out of 26, voted for Sanders. “It was also emotional,” she tells Fortune. “Other members of the Vermont delegation were tearing up after I took the mic, which is understandable because we’ve all put so much into Bernie’s campaign.” The Vermont senator was also seen crying earlier in the roll call when his brother Larry, a delegate for Democrats Abroad, cast his vote for Sanders in a heartfelt speech.

Still, the Vermont delegation opted to support the tactic, creating a moment of solidarity at what had been a fractious convention. As O’Leary puts it, “party unity is of the utmost importance.” The teenage high school graduate has pledged to vote for Clinton in November. “[I] am more comfortable doing so now that Bernie has pushed the party further left and catalyzed a progressive platform,” she says.

O’Leary campaigned to be a DNC delegate towards the end of her senior year by making flyers and meeting “as many people as I could, and was ecstatic (and a bit surprised!) to win the election,” according to her GoFundMe page. (As a fee, GoFundMe gets 5% of the $2,000 O’Leary raised, or $100.) She plans to attend Rice University in Texas this fall.