When Beltane was killed in a freak hunting accident, Guinevere was heartbroken. She had watched Beltane grow up from such a young pup, and to see her pass away so young hurt the entire pack. So when her first three pups were born and one of them looked so similar to the late pack member, she decided to give her daughter Beltane's name to honor her. Thus started the tradition in the Sleepers Pack of honoring lost pack by reusing their names in new wolves.
It might be said that Kvöldið is Beltane reincarnated, or that using Beltane's name is invoking her spirit in this new wolf. Whatever the case, Kvöldið more than lives up to the name she carries and continues to make the pack proud to this day.