Det. Olivia Benson (Mariska Hargitay) has helped countless victims and survivors as a detective, now captain, of the Special Victims Unit. And she draws much of her strength and inspiration from her late mother, Serena. Though she was only in a few seasons, Benson’s relationship with her mother is a major driving force for her character. Here’s what to know about the woman who created Olivia.

A split of Captain Olivia Benson from Law and Order SVU and Elizabeth Ashley

Serena Benson only appeared in one episode

In the series premiere, “Payback,” we see Olivia and her mom Serena, played by actress Elizabeth Ashley, at dinner in a restaurant discussing Olivia’s current case. Serena is concerned for Olivia’s emotional state working in the Special Victims Unit because of their family’s connection to sexual assault. Olivia is the product of rape, and appears to have known this information for most of her life. They share a tender moment, and this is the last we see of Serena. (Elizabeth Ashley had previously appeared on a 1994 episode of Law & Order.)

However, it’s not the last we hear of her, and their relationship is more fraught than initially depicted. Over the seasons, Benson makes a few confessions about her upbringing. Serena was an alcoholic who was sometimes abusive and had a love-hate relationship with her daughter, who reminded her every day of her rape.

Serena was an English professor at the fictional Hudson University, and teenage Olivia had a relationship with one of her students. After the two announced their engagement, mother and daughter got into a fight that turned physical.

How Oliva’s mom, Serena Benson, died

Olivia and Noah Benson walk down the street together on Law and Order SVU episode 2310

Early in Season 2, Benson reveals that her mother, while intoxicated, fell down the stairs while leaving a bar and died as a result of her injuries.

However, despite all her trauma, Benson is able to create something like a happy family. She is a devoted mother to her adopted son, Noah Porter Benson. Noah (Ryan Buggle) is also the result of a rape, and Olivia became determined to take care of him after his birth mother died. Noah’s early life was marked by tragedy and trauma, but with a protective mother like Benson in his life, he’s been able to grow up feeling not only safe and secure, but also happy.