arah Michelle Gellar has taken on husband Freddie Prinze Jr.'s surname -- five years after the couple wed.

The "Buffy the Vampire" star has changed her famous three-part moniker as a fifth wedding anniversary present to her actor husband.

A source tells Usmagazine, "She officially changed her name to Sarah Michelle Prinze in honor of the occasion.

"On their anniversary, she showed (Freddie) her new driver's license. It was so sweet."

source