The untimely death of former child star Michelle Trachtenberg has left fans reeling, as the actress effectively grew up on-screen with iconic roles in projects like Harriet the Spy and Buffy the Vampire Slayer.

Trachtenberg was found dead in her New York City apartment Feb. 26 at the age of 39. ABC News reports the actress “may have been experiencing complications” after recently undergoing a liver transplant, but authorities say her death is “not being investigated as suspicious.”

Trachtenberg largely stayed out of the limelight in recent years, bar some notable exceptions, but she left an indelible mark on television.

Her career began with an appearance in Law & Order in 1991, kicking off a prolific career with appearances on Clarissa Explains It All, All My Children, Weeds, Criminal Minds and more. She also led movies such as Ice Princess and Eurotrip. But it’s worth looking back at some of her most notable credits; though she largely played supporting roles, Trachtenberg left an undeniable impact on any series she touched.

The industry lost an icon today. Scroll down to learn more about Michelle Trachtenberg’s movies and TV shows.

Gossip Girl

Georgina Sparks will go down in history as one of the best villains in television history. Trachtenberg’s iconic turn as the schemer began in Gossip Girl Season 1, Episode 15 when Georgina is introduced as an old friend of Serena’s (Blake Lively) who is nothing short of a bad influence. Though they make amends, Georgina quickly reveals in the episode that she has much more nefarious motives for re-entering Serena’s life, setting the bar for Georgina’s evil ways.

Trachtenberg returned to the show several times between 2008 and 2012, in part thanks to her compelling performance playing a character who was as tragic as she was likable. She also reprised the role for the Gossip Girl reboot, marking the very last performance of her career.

Mercy

In 2009, Trachtenberg landed one of the lead roles in the short-lived NBC drama Mercy, which followed three nurses juggling their personal lives with the drama of working in a hospital. Trachtenberg played Nurse Chloe Payne, a naive recent graduate who gets overwhelmed by the hospital’s high-stakes environment. Though the show was not quite well received when it aired on NBC, Trachtenberg’s performance is worth watching as the actress has shown before that she can toe the line between good and bad.

Six Feet Under

Before she played the egotistical Georgina Sparks, Trachtenberg showed off her mean girl energy with a brief arc on Six Feet Under Season 4. She starred as Celeste, a teen pop sensation who hires Keith (Matthew St. Patrick) to become her body guard. The high maintenance pop star eventually sleeps with Keith, but fires him after he comes out to her.

Robot Chicken

One of the final acting credits of Trachtenberg’s career was in Adult Swim’s Robot Chicken, in which she briefly reprised one of her earliest roles as Harriet the Spy herself.

The 2018 episode catches up with the spy 20 years after the iconic movies working as a professional spy as she tries to expose the United States government for secretly surveilling citizens. Though she successfully carried out the “biggest data theft in U.S. history,” it’s clear Harriet’s better days as a spy are behind her as she’s been exiled to Moscow.

Buffy the Vampire Slayer

Everyone remembers the profound confusion of tuning into Buffy the Vampire Slayer Season 5, Episode 1 and meeting Buffy Summers’ little sister, Dawn, for the very first time. Trachtenberg doesn’t miss a beat in her debut on the show. Though everyone is deluded to believe that Buffy has always had an annoying yet lovable little sister, Trachtenberg and Gellar’s undeniable chemistry really drives the concept home for viewers.

Dawn’s true origins are later revealed on the show. But her seamless integration into Buffy’s life — and the rest of the characters’ — makes it hard to believe there was ever a Buffy without Dawn.