Mulder had a rather strained relationship with his parents Bill and Teena Mulder, not least thanks to the X-Files. Initially, he had no idea his father was involved in the conspiracy and Samantha's disappearance. Bill, who became disenchanted with the shadow government and his own role in the conspiracy, eventually approached Fox about his past deeds, but was shot and killed by Alex Krycek – working as an assassin for the Syndicate – before he could reveal any great amount of information. Over the next few years, Mulder got into several conflicts with his mother while trying to discover the extent of her own knowledge of his father's precise involvement. Teena dies of an apparent suicide, when the stress of Samantha's abduction finally becomes too painful.