Bulda

Bulda is a female troll with special powers featured in the 2013 animated film Frozen. She is the adoptive mother of Kristoff and Sven. She is voiced by Maia Wilson.

Role in Frozen
Bulda is shown towards the beginning of the film, when The King and Queen of Arendelle are rushing to save Anna, after she is struck by Elsa's powers. A young Kristoff and Sven arrive at the scene, where Bulda encounters them. Bulda proclaims, "cuties--I'm going to keep you." This could be interpreted as her "adopting" the two.

Bulda appears later in the film, during the second meeting with the trolls and the "Fixer Upper" song sequence. Bulda, along with the other female trolls, assist in dressing Anna in her troll wedding outfit. Bulda aids in orchestrating the spontaneous wedding of Kristoff and Anna, taking on the role of a meddlesome mother (Kristoff being her son).

Trivia

 * The Junior Novelization misspells her name as "Hulda".
 * Bulda seems to be very fond of Anna, since she knew Anna and Kristoff would eventually get together.