This quest becomes available after you’ve completed Reporting on East Anglia. Randvi informs Eivor that Svend has died in his sleep, and Tove has taken the loss hard. You should check on Tove in the woods west of the longhouse, where Svend is now buried.
When you speak with Tove you’ll have a number of dialogue options, but none will significantly impact the course of the conversation. Eivor will comfort Tove all the same. When the scene ends, be sure to interact with the burial mound to speak with Svend. You can return to the grave at any time and interact with it.