A pas de deux is about to become a pas de trois for two married principal dancers with the National Ballet of Canada. The company has announced that Heather Ogden and Guillaume Cote are expecting their first child in December. The Toronto-born Ogden is currently on maternity leave and is slated to return to the stage next June. Cote, who hails from Lac-Saint-Jean, Que., has been a principal dancer since 2004. Ogden has been a principal dancer since 2005. The couple met at the National Ballet when they joined the company in 1998.