Trailer Choir lead vocalist Marc "Butter" Fortney married Emily Robertson, a member of the Carter's Chord vocal group, during a surprise ceremony Monday night (Sept. 6) at 12th & Porter, a club in downtown Nashville. Friends and family were told the event was a birthday party for Fortney. Trailer Choir and Carter's Chord were among Toby Keith's first signings when he launched his record label, Show Dog Nashville, which now operates as Show Dog-Universal Music.