Time travel is used in Kindred in order to address themes of family and race. When Dana travels through time, she both takes her family (her husband, Kevin) with her and appears in the past in the presence of her ancestors.
Dana quickly learns that her ancestors are both white plantation owners (Rufus Weylin) and slaves (Alice Greenwood) in nineteenth-century Maryland. Alice is forced to have children by Rufus, giving birth to Hagar Weylin and creating the line that will eventually lead to Dana's birth. Dana notices the similarities between herself and Alice, realizing that Alice's life could have easily been her own if she'd been born in the nineteenth century instead of the twentieth.
We also meet Rufus Weylin's parents, Tom Weylin and Margaret Weylin. Tom is a cruel man, quick to violence toward anyone who angers him. Dana comments that Tom "sounded like a man who worked at inspiring fear" ("The Fire," part 2). Margaret's actions are unpredictable, swinging between kindness toward those around her when she's under the influence of opium and abuse when she is not. She beats Dana the first time she meets her, assuming that Dana has "killed" Rufus when, in actuality, Dana has saved him from drowning ("The River"). This is just the first incident in a pattern of Margaret lashing out in anger against the slaves on the plantation.