(Warning: Major spoilers for Episode 10 of House of Cards Season 4.) There was a new character introduced to House of Cards viewers in Season 4 that gave us a lot of answers as to why Claire is the way she is. Early on in the season, we meet Claire Underwood's mom, Elizabeth Hale, who is just as regal, stubborn, and powerful as her daughter. We learn that Elizabeth has cancer, and it's not looking good for her. Claire's mother's health rapidly declines over the course of the season, eventually leading to her death in Episode 10. But, her death wasn't just any death, which might leave viewers wondering how Claire's mom Elizabeth died on House Of Cards.
In Episode 10, Claire returns to her mother's home in Texas (with Tom Yates) and spends her final moments making amends with a woman she didn't seem to have much of a relationship with. It really sinks in that Claire's mom doesn't have much time left when she asks Claire to do "something" for her. Initially, Claire says she can't do it, but later agrees to help her mother in assisted suicide. With Tom by her side, Claire administers a lethal dose of something through a syringe that slowly puts her mother to sleep.
The two women, no matter how different their lives may have been, seemed to come together in this moment. Despite it involving death, Claire and her mom look like they've never been closer. In their minds, they're both acting selflessly for the other. Elizabeth believes that her death will "help Claire win," and Claire thinks that she's doing what her mother wants her to do, despite her own wishes.
Both women, despite their differences, share one major thing in common — they're both incredibly strong. Elizabeth put up the best fight she could late in life, while also trying to further her daughter's career — despite the strange paths she took. Claire is just about ready to do anything for power, but proved that her strength goes beyond her negotiation skills.