Marilyn is the biological mother of Olivia Dunham and Rachel Dunham in the Alternate Universe. Her daughter Rachel died during childbirth with her granddaughter, who also died. She has a close relationship with her other daughter, Olivia.
When Marilyn arrives at her house and hugs Olivia Dunham (whom she thought was her daughter). Marilyn tells her that she came back because she heard what had happened to her and she is scared. Olivia claims that she is not her daughter and breaks off the hug. Olivia insists that her mother died when she was 14 and the place is not her home. Marilyn insists otherwise and challenges Olivia how she finds out about the place. Olivia stops freaking out and realizes that she helped to paint the house with yellow color. Marilyn reminds Olivia that the place is her safe house and they hug. When Agent Charlie Francis (Alternate Universe) arrives at the Dunham residence, Marilyn tells Charlie that Olivia is in the house. Olivia is sitting in the sofa and greets Charlie. ("Olivia")
In Amber 31422, Marilyn visited her daughter and gives her a hug. Marilyn reminds her daughter that it is Tuesday. Olivia apologizes for not making time for lunch. Concerned for her, Marilyn asks if she is okay. Olivia confesses that she is tired. A vision of Peter interrupts her of a story of Nina and Gina, twins with different intelligence but they both always get straight A's. Marilyn snaps out of her. Olivia realizes something; she apologizes to her mother for leaving her alone. In Bloodline, she and Olivia were visited the doctor's office to see if Olivia has VPE, but Marilyn is worried that 'Viral Propagated Eclampsia will kill Bolivia and her infant son, like it killed her other daughter, Rachel, and her infant daughter. Later, She visited her daughter and her new grandson in the hospital and was happy that they were both okay.
- This Marilyn doesn't have an abusive husband.
- "Sweetheart... this is your home. This is your safe house." - (to Olivia, unaware that she is comforting a version of her daughter that is from a separate universe)
- "To tell you the truth, all you need to do is love him. And you can figure out the rest as you go on." - (to Bolivia, reassuring maternal advice to a nervous new mother)