In twilight the book who is emmet?

Emmett Cullen, born Emmett Dale McCarty in 1915, was a vampire and member of the Olympic Coven. He was the husband of Rosalie Hale and the adoptive son of Esme and Carlisle Cullen, as well as the adoptive brother of Jasper Hale and Edward and his adopted sister Alice Cullen. (source: http://twilightsaga.wikia.com/wiki/Emmett_Cullen)