Ylva is wife to Halvar, chief of the Viking village Flake, and mother to protagonist Vic. As the chief's spouse, she commands respect within the community and often oversees village affairs while the men embark on expeditions. Her personality is assertive, bossy, and occasionally critical, especially in dealings with her husband and fellow Vikings.

In the 2019 film *Vic the Viking and the Magic Sword*, Ylva plays a significant role when Halvar accidentally transforms her into a golden statue using a magic sword stolen from his rival, Sven. This act ignites the film's central quest: Halvar and the villagers must journey to the mythical Bifrost bridge and Asgard to reverse the enchantment, seeking the sword's origin with Odin. Petrified for much of the narrative, Ylva embodies the consequences of the village's unchecked greed and ambition.

Her relationship with Vic reflects maternal support, though Ylva primarily functions as the household's stabilizing force rather than an active participant in the Vikings' adventures.