I have read the manga, but I will stick to facts we know from the anime just to make it easier. Spoilers for the anime but not the manga.
Carla could barely hear the sound of her own spine cracking over her own screams as the giant hands harshly bent her back. She could slowly see the giant teeth nearing her body before her vision went dark.
When her vision returned, the pain had completely gone away. She was staring up at a pure white ceiling. She reached a hand to her face to make sure this was real, and felt tears slipping down her cheaks. She turned to the side, seeing that her husband, Grisha, was still sleeping, his back facing her. She quickly wiped the tears from her face and slowly got out of bed, careful not to wake her husband. She checked the time on the small clock on the wall to see that it was only 5:21 in the morning. The sun hadn't even risen yet. She got dressed and headed out of her bedroom. When she opended the door, she was met by a blast of cool air from the hallway. Her and Grisha's bedroom always seemed to be warmer than the other rooms. She shivered and rubbed her arms while tiptoeing down the hallway to the rooms belonging to her children Eren and Mikasa. Mikasa had actuall been adopted by the small family after her parents were murdered by three kidnappers, but she fit in so well, that Carla already considered her part of the family. She slipped first into Mikasa's room and saw her sleeping soundly before peeking into Eren's and seeing the same. She let out a sigh of releif to see them both safe after the horrible dream she had had.
She considered trying to fall back asleep, but memories of the dream flooded back and she decided to simply make breakfast instead. After a couple minutes of cooking she glanced back at the hallway that held their bedrooms with a confused look on her face. By now Grisha should have woken up. He had to leave for work in 45 minutes and he still hadn't eaten breakfast. She turned of the stove to make sure the food wouldn't burn before speed walking down the hallway and back into the master bedroom. Grisha was still sound asleep on his side. Carla scowled and walked over to the bed. She gently shook his shoulder while muttering his name. His breathing stayed steady and his eyes open even a peek. She scowled and shuffled out of the room. He was probably playing some sort of trick on her.
Back in the kitchen, she turned the stove on and continued to cook. The leftover horror from her dream had her already imagining why her husband wasn't waking up, but she decided to ignore the delusions and go on with her morning. 15 minutes later, she was sitting in the living room reading a book, when a chill crept its way up her body. She looked up to see the seemingly empty house before her. She shivered, despite the warm air. The house had never felt this empty before, even when she was the only one home. She set her book down and went to go check on the kids. They only had to go to school at 8:00, but Mikasa usually got up pretty early. For what reason, Carla was unaware, but the girl liked to sit in the living room and simply stare out the windows until Eren woke up.
Carla remembered the first night Mikasa had spent in their home. Despite them having set up a room for her, she refused to leave Eren's side, resulting in the two nine-year-olds having a "sleepover" in Eren's room. Grisha had taken the blankets from Mikasa's bed (used to be the guest bed) and put them on the floor for her to sleep on. However, when Carla came to wake them up in the morning, Mikasa had cuddled up beside Eren, her face burried in the red scarf. The two had gotten along great, and when Eren introduced Mikasa to his best friend Armin, they seemed to get along as well.
Carla smiled at the fond memories and shuffled her way back to the hallway. She peered into Mikasa's room and saw that she was still asleep. Carla knew it was selfish, but she was lonely and thought Mikasa wouldn't mind if she woke her up. "Hey, Mikasa? Dear? Are you awake?" Carla called, distrupting the silent atmosphere of the room. Mikasa didn't move. Carla's heart raced for a second, but focused on Mikasa and noticed her chest slowly rising and falling. Carla cautiously walked to the bed and shook Mikasa's shoulder gently. "Mikasa? Are you okay?" The little girl still didn't wake up. A frightening idea crossed Carla mind and she rushed into her husband's room. "Grisha!" She yelled, running over to the bed. She shook his shoulder, not bothering with being gentle. "Grisha!" By now, her yells should have awoken Eren, but based on what was happening, she knew he would still be asleep. Despite that, she ran to his room. "Eren!" She yelled, "Eren! Wake up!" She could feel a tear make its way down her face.
She ran into the main room and picked up her cell phone that was sitting on a table next to the chair she had been reading in. She ran back into Mikasa's room. She managed to pick up the frail little nine-year-old, but the girl still didn't awaken. Her head lolled back, her neck limp, as Carla carried her into the master bedroom. Carla set her adopted daughter down next to her husband and then hurried into her son's room. After Eren was safely next to Mikasa in the bed, she sat down next to the three of them and called 911.
"911, what's your emergency?" The operator asked.
"Uh, yes, hello. My name is Carla Jeäger and my husband and children won't wake up." Carla said as quickly as possible.
"Can you tell us your address please?"
"Yes, it's 6769 East Sare Road, Shiganshina, Maria."
"Thank you. We will be right there."
"Thank you!" Carla cried before hanging up and bursting into tears.