My Crazy Blacklist Theory
Everyone seems to think that Red is Elizabeth's father but I think that's too simple. I think he's her husband's father. Red had a daughter. Daughter grew up and transitioned to male, fell in love with Elizabeth and got married without telling her about the transition.
Think about it. He said that her husband was keeping something from her. She said she wanted to have a biological child but they are adopting, maybe because he can't have children with her? His dad got interested in Elizabeth as the women his child was with, but when he found out the she was in the dark about his son's transition surgery he decided that he was on his daughter in law's side rather than his son's.
















