|Eren! What are you thinking?! Do you have any idea how many people have died outside the Walls?!|
|— Carla to her only son, Eren|
Carla had brown eyes and black hair. Her hair was rather long, kept tied loosely to the side on her right shoulder with a dark red tie and only a few short hairs around her ears and forehead were loose. When she was seen inside her home, she wore a cream-colored sweater with frilled sleeves and a long red skirt with a white apron and small tan boots.
When Eren wanted to join the Scout Regiment, Carla forbade him on the grounds that it was too dangerous, showing her motherly care. She seemed to genuinely care for Eren's safety, and had been known to be protective of her family, enough to put them before herself when Eren and Mikasa were in potential danger for attempting to rescue her. However, once her children left earshot, she whispered that she did not want them to leave her alone to die and continued crying until her death.
During her youth, Carla worked as a waitress in a bar that Keith Sadies frequented. One day, Keith brought along Grisha Jaeger, who had recently been found lost outside of the Walls. Carla reprimanded Keith, thinking that he wanted to beguile Grisha into joining the Scout Regiment, but both men denied this.
Sometime later, Carla became ill with a disease that plagued Shiganshina and was urgently taken by Keith to Grisha, who had become a doctor. However, Carla was more worried about her parents, but Grisha ensured her that everyone would be fine. Grisha managed to save Carla and her family, and Carla hugged him as she rejoiced in tears.
They soon fell in love, and sometime later married and had a son named Eren. When Keith returned from an unsuccessful mission as commander, he approached Carla with a young Eren and she expressed her and Grisha's worry for him. Out of spite, he accused her of being ordinary and lacking in imagination. However, Carla simply stated that some people do not have to be special or greater than anybody, adding that existing on its own was special.
Carla is first shown forbidding Eren to join the Scout Regiment after Mikasa spoke of Eren's desire to join the military. Though Eren's father Grisha remained passive and even insistent of Eren's ambition before leaving the house, Carla continues to attempt to convince Eren otherwise, leading Eren to yell at her and run off to ignore her protests. Upon this, Carla tasked Mikasa with looking out for Eren, saying he needed to be protected from himself.
During the invasion of Wall Maria, the Colossal Titan breaches the Wall of Shiganshina District by kicking at its outer gate, and some of the flying debris falls on the Jaegers' house, destroying it with Carla inside. She is trapped and her legs are crushed. Eren and Mikasa attempt to free her, but they are not strong enough to lift the beams holding her down. She begs them to leave because of the Titans swarming the city as one Titan is visibly approaching their house.
Soon, Hannes arrives, initially declaring that he would save the three of them from the approaching Titan, despite Carla's protests that he should grab the children and run. However, Hannes loses his nerve at the frightening appearance of the Titan and decides to take the children to safety instead, abandoning Carla under the wreckage as she requested.
Against Eren's desperate protests, Carla screamed to her children that she loved them and pleaded them to stay alive. Once the three were on the run and out of earshot, Carla mutters that she does not want them to go, but covers her mouth with her hand so that the children cannot hear her last words. The Titan pulls her from the debris and squeezes her in its hand, causing her innards to spew out of her mouth. Just after Mikasa looks away, it devours her as Eren watches in horror.
While Eren recuperates after the Assault on Stohess battle, he remembers when his mother told him that he is a man who needed to show some restraint and not get into fights, with Mikasa always coming to his rescue. She reminded him that he also needs to be there for Mikasa.
- Grisha Jaeger - Grisha was Carla's husband. He was a well renowned doctor known most notably for single-handedly curing an epidemic that had affected the town. When Carla learned that Eren wanted to join the Scout Regiment, she pleaded Grisha to change his mind, but Grisha said that there was no point in stopping an inquisitive mind like Eren's.
- Eren Jaeger - Eren was Carla's only son. She felt a deep love for him, seen when she told him not to join the Scout Regiment because it was too dangerous. Also, when she was trapped under the debris of their house, she ordered Eren and Mikasa to run away and leave her behind so that they could escape from the Titans. She also told Hannes to take them and run, feeling relieved and thanked him when he accepted.
- Mikasa Ackermann - Carla relied on Mikasa to keep an eye out for Eren, trusting her enough to pull him out of trouble. When Mikasa was first accepted into their home, Carla showed that she was comfortable with Mikasa's company. The two often did chores together in the home such as washing dishes and they bonded over this. When Mikasa struggled to save her, and when she was taken away, Carla painfully called out to her in her final moments, worried for her safety. She greatly cared and worried for Mikasa, despite her independence and strength. Carla's death had a deep impact on Mikasa who vowed to uphold the promise she made to her in protecting Eren.
- Carla is the first character in the series who is shown being eaten by a Titan.
- Carla has a character song in Linked Horizon's Shingeki no Kiseki album, 14 Moji no Dengon (14-Lettered Message).