Photo: Shareif Ziyadat/Getty; Taylor Hill/WireImage

Country duoDan + Shaywere both on board with serving as impromptu wedding singers for their collaboratorJustin Bieberlast month.
Dan Smyers and Shay Mooney were guests at Bieber’s wedding to Hailey Baldwin in Bluffton, South Carolina, where they performed theirnew song “10,000 Hours”— which Bieber cowrote and lends vocals to — for the first time in front of a live audience.
“We had never rehearsed it,” SmyerstoldEntertainment Tonightat an event in Nashville on Wednesday. “We obviously recorded it in the studio, but we never played it live in front of actual human beings. [But] Justin was like, ‘Sing ‘10,000 hours,’ we’re like, ‘OK, we’ll try.’ ”
Mooney joked the pair were “just making up the words,” Smyers adding: “It was good though, it was really fun and people were out on the dance floor rocking.”
Dan + Shay.Frazer Harrison/Getty

The event marked the second time the Biebers married each other,first tying the knotmore than a year ago at a N.Y.C. courthouse. To celebrate with friends and family, the happy couple opted to hold thelarger ceremonyon Sept. 30.
“It’s awesome to get to attend their wedding and it was a blast,” Smyers says. “It was a really good time.”
About 154 guests were in attendance, includingKendallandKylie Jenner,UsherandJaden Smith, a sourcepreviously confirmed to PEOPLE.
“We’ve always wanted to do some collaboration with [Bieber] and we wrote the song and thought it would be perfect and sent it over to him not knowing what would happen,” Mooney toldET. “He loved the song; he’s in a similar place in his life, just got married, and so it was really cool to have that moment all together.”
Catherine Powell

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“The timing of it worked out and we still can’t believe that it happened,” Mooney toldET. “I’m waiting to wake up tomorrow and [find out] like, ‘That actually never happened to you guys.’ “
source: people.com