A/N: At last, here is the final installment in this four part time travel saga. Thank you so much for sticking with me and being so enthusiastic. I really do appreciate it. Special thanks to the guest who submitted this prompt. I had an incredible time writing it, and hope you all enjoyed it just as much! The poll is still up for voting and the next prompt will be started soon. :)

I'd love to hear your thoughts on Part 4!

Prompt: Kara and Alex somehow time-travel to Krypton and Alex meets Kara's parents. Together the four of them have to figure out a way to get Alex and Kara back to their time before Krypton explodes.

Time Travel - Part 4

"This isn't Earth," Alex said immediately, voice sharp.

Kara's eyes snapped open, she was struggling to breathe through the sob stuck in her throat. She swallowed hard and forced herself to look around. "That's because this is still Krypton." In the dark night sky, a white pod shot through the stars. "And it's going to explode within minutes, because that's Kal-El's pod."

Alex blinked, looking down at the time traveling device in her hands. Her heart was thundering in her chest.

"Alex, put more of the mineral in!" Kara yelled, shifting her gaze between her sister and the distant launch pad. At this very moment she was saying goodbye to her parents, while Krypton's core was mere minutes from exploding.

"I thought it wasn't supposed to work after midnight," Alex shouted. With unsteady hands she fought to tug the excess mineral from her pocket.

"It traveled time, it didn't undergo the pressure of the unstable core." Alex could hear the tears brimming in her sister's voice. "It has to work, it has to." She pulled shaking fingers through her blonde hair.

Another white object pierced through the sky. Young Kara's pod.

"That's me, you've got to do it. Just put it in!" Kara screamed, her voice hoarse, her throat raw. "Put all of it in!" she cried and Alex jammed the rest of glowing purple substance into the small device.

They watched as it vibrated at the same time the ground beneath them grew hot and turned crimson with heat.

"Grab my hand!" Alex cried, curling her fingers around Kara's arm and grabbing the device.

For a moment, amidst a suffocating darkness, Kara wasn't sure if they had died or if they were time traveling, but then her feet met solid ground and she could feel the air buzzing and the presence of her powers returning—for the first time they made her feel jittery and sick.

"What happened? Why didn't it work the first time?" she cried, seeking out Alex in the darkness.

"I don't know," Alex panted and drew the back of her hand across her forehead, feeling sweat. "But that was close."

Kara nodded and fell silent, she stared down at the object in her hand. Her mother's favorite necklace. Simple and silver and still warm from her mother's skin. Kara latched it around her neck and looked up at Alex.

The brunette pulled Kara into her arms and held her as tears spilled from Kara's cheeks and her body shivered. It just felt like everything was gone. Alex rubbed her sister's back and with each cry, Alex tugged her closer, until Kara's tears stilled.

"I love you," Alex whispered, to which Kara responded with a small, little quivering exhale of breath as her shoulders sunk and her eyes, still wet, stared into the distance.

Alex squeezed Kara's shoulder gently and they left the cave without any more words, a few minutes after the exact time they'd zapped out of it, in what felt like a lifetime ago.

Alex guided Kara out of the dark area and into the SUV they'd driven over. They rode in silence as Alex eyed her sister carefully and the blonde leaned her head against the window, gazing through the glass.

As they completed the drive, Alex called J'onn, needing to update him on the situation as quickly as possible and hoping to get out and get Kara home without having to waste time answering questions at the DEO.

"We're here," Alex said softly as they pulled up to the base. For a moment, she thought her sister was sleeping, but Kara rose from her seat and rubbed her eyes as she wordlessly exited the car. She closed the door with half the strength she usually did. Exhaustion was heavy in her bones, each moment slow and difficult as she walked.

They were checked over by a med team and deemed clear within minutes. Kara took a seat on a rounded metal bench, Alex remained standing, pacing as she waited for J'onn to appear.

He arrived a moment later, stepping toward Alex. "Danvers, we need to talk. I need a debriefing."

She sighed and ran a hand over her face, sending a worried glance at Kara, whose head was bowed, gaze trained on the floor as she sat, appearing oblivious to the conversation in front of her. "Can't it wait?"

J'onn shook his head. "I'm afraid not." He saw the concern in her eyes as she stole another look at Kara and guided him away from the blonde. It wouldn't do much if Kara was using her superhearing, but in Supergirl's current state, Alex didn't see Kara caring enough to even try.

"Please, can I stay with Kara? She needs to go home, she needs to rest. I don't want her to be alone. Look at how sad she looks."

"I'm sorry but the DEO needs you to recount what happened, this will be the last time, but we need it immediately. Kara can go home, we'll have you joining her as soon as you're finished."

Alex looked over her shoulder, saw Kara running her fingers along the hem of the skirt to her Super Suit. "Kara," Alex called, gesturing with her head to come over. The blonde stood up, made her way shakily to her sister and J'onn.

"You wanna go home?" Alex asked, looking at Kara with concern shining in her eyes.

Kara shrugged, finger rising to fiddle with her mother's necklace. "Okay," she said softly before giving a small nod.

"I have to stay here for a little while, but if you want I'll figure out a way to get around it," Alex said, giving a half shrug to J'onn as he shook his head.

"No, it's okay. I'm fine, really." Kara hoped they couldn't tell how much she was trying to keep her voice steady. She wanted to go home, collapse onto her bed, nestle under her sheets and lie there for the next few years, maybe forever.

"Are you sure?"

Kara nodded. "Don't worry about me. I think I'll just sleep for a bit."

"All right," Alex agreed even though her heart was clenching. She gave her sister a smile and pulled her into tight hug. "I love you," Alex whispered into the blonde's ear.

"I love you, too," Kara said, stiff and tired in her sister's arms.

They parted ways and Kara gave Alex a soft wave and a 'see you later.' She couldn't bring herself to say another goodbye.

/

Kara entered her apartment with a heavy sigh and looked around. She dropped herself onto her couch and curled in the corner, knees tucked against her chest, arms wrapped loosely around her legs. She rested her cheek again the fabric, gazing out her apartment window without really looking at anything. Her fingers were glued to her mother's necklace. She rubbed it between her fingers. Back and forth. Back and forth. There were no thoughts of CatCo or work or Supergirl duties, just an impossible sadness as she tried to breathe with the gaping hole of anguish that burned in her chest. Her heart was still thundering, exhaustion still weighing heavily on her body.

Despite her efforts to stay awake, her eyelids closed, her head dipped forward and she slipped into sleep.

/

Somewhere just past four in the morning, Alex let herself into Kara's apartment. "Hey," she said softly, taking a few steps toward Kara, where she was still positioned on the couch. "I thought you might be sleeping now. What happened?"

Kara shrugged—she seemed to be doing a lot of that lately—before responding, "I was, but I woke up just after an hour and I couldn't fall back asleep."

Alex nodded sympathetically. "Maybe if you change into your pajamas and try your bed you'll have better luck?"

"Maybe," Kara said, but made no move to get up until Alex nudged her. "Come on, at least get changed, you'll feel better."

With a slow nod Kara stood up and disappeared into her bedroom. She returned a moment later clad in pajamas now, but with tears burning in her eyes.

"Hey, hey, hey, what's a matter?" Alex rushed to her sister and took Kara by the shoulders, noticing the blonde was clasping something in her hand.

Kara gave a sob as a response and then she was folding in on herself.

It was entirely different from Kara's silent weeping when they'd first arrived back on Earth; this time her sobs were loud and hard, so forceful that Alex was afraid Kara might make herself sick.

Alex didn't say any words, just pulled Kara into the firmest hug she could muster, hoping it might convey how loved the younger girl was, hoping it might help Kara remember that she wasn't alone.

"I want to take it," Kara said through tears, shoulders shaking violently.

"Take what?" Alex asked, pulling away so she could look at Kara.

The blonde opened her hand and extended her palm, revealing a small white pill. The same pill her parents had taken just hours before but worlds away.

"I don't want to remember," Kara cried out.

Alex observed Kara, saw her hair a mess, her eyes red rimmed and watery, her features crumbling as her body heaved with the power of each sob. She thought she might cry herself to death. "No," Alex said, swallowing hard and looking Kara in the eyes. "I understand that you're upset and you're hurting, but you don't mean that."

"What if I do?" Kara asked and gathered a handful of hair in her fist, doubling over with the pain radiating through her body, sniffling. "What if it's finally too much?"

Alex shook her head. "Sometimes you struggle and stumble and crash and fall, but the Kara that I know doesn't give up, she doesn't take the easy way out just to temporarily get away from feeling. It hurts now, I know, but someday you'll be glad you got to see them again, you'll be thankful for those extra moments."

"That's not me. I'm broken, Lex. I'm not strong enough to relive this all over again."

"No, Kara, no. You're wrong." Alex knelt down so she was eyelevel with her sister.

"I can't do it," Kara said, her voice a quivering breath. "I don't-don't care if-if it's wrong. I don't want to remember." Kara hit the floor with her fist and the wood splintered slightly. With hands and knees pressing into the ground another sob wracked her frame. "I wish—I wish I'd ne-never even gone back th-there."

Alex grabbed the blonde's shoulders, pulled her sister close. "That's not true."

Kara whimpered and cried and ducked her head. She heaved a heartbreaking breath and was silent for a long time. "I know," she said finally in a watery exhale. "I know." Without looking up, she extended her hand to Alex, allowing her big sister to take the pill from her shaking, pale hand and pocket it to be returned to the DEO.

"I just miss them so much," Kara said, on the verge of hyperventilating. "It's like I can't think, I can't breathe, I can't feel anything but this pain in my chest."

"Let's stand up then, come on," Alex said and helped Kara to her feet, pulling her off the wooden floor.

"I'm sorry," Kara breathed and crumbled against Alex. "I didn't mean it, I didn't mean any of it—I just—I'm sorry—I'm so sorry."

Alex held her sister so tightly she could feel Kara's chest rising and falling with each sob and trembling inhale. She could feel Kara's warm breathe and hot tears; could feel Kara drop her head against Alex's collarbone and press her face into the fabric of her sister's shirt. "I know," Alex said and ran a hand over Kara's hair. "You don't have to be sorry."

"It feels—it feels like I'm n-never going to be hap-happy again."

Alex gave Kara another squeeze, cradled her sister's head so her blonde locks bunched up and the tears falling from Kara's cheeks dripped onto Alex's shoulder. Alex leaned back to look at Kara and tap her chin up so their eyes met. The brunette pushed Kara's hair off her wet cheeks, tucked it gently behind her ear and thumbed away her tears. "But you know better than anyone, that that feeling will go away."

Kara squeezed her eyes closed, producing more tears, and nodded. "I know." She took a long, shuddery deep breath. "I know," she repeated, this time her voice wavered less.

A sigh worked its way through her lungs and she dragged her fingers across her cheeks, wiping away the new tears that had fallen.

"You'll be okay," Alex said and pulled Kara close again. "I know it doesn't feel like it now, but you'll be okay. It'll just take time."

Kara nodded, sniffling as Alex smoothed her hair and held her securely. Moonlight flooded the apartment and glinted off the furniture. The foot of Kara's pajamas leg gathered beneath her heel. She felt small and little again, but seeing her parents also made her feel bigger, more capable, in a different kind of way. "I'm glad I got to see them," Kara whispered.

"I know."

"And I'm glad you got to meet them."

"Me too," Alex said. "It was truly a pleasure to meet the people that got together, had a good time, and made my baby sister."

"Alex!" Kara said, a soft giggle lacing her voice as she gently swatted Alex's arm and wiggled away, blush rising on her cheeks. "You're gross."

Alex smiled, encouraged by her sister's laugh. "Jeez, Kar, get your mind out of the gutter. I totally didn't mean it that way. Your parents are lovely people… you," Alex wrinkled her nose at Kara, "maybe not so much."

Alex ducked as Kara threw a pillow in her direction. "You're annoying," the youngest Danvers called out. "And also, I'm hungry."

"Yeah, I figured that was coming," Alex said, fondly rolling her eyes and tossing the pillow back to Kara. "I'll make you something."

"I love you," Kara singsonged, sitting crisscross on the couch and smiling up at Alex as she made her way into the kitchen.

"I'm going to make you waffles, which on earth is, like, the same thing as saying I love you," Alex said, stopping by the couch to ruffle Kara's hair. "Which I do."

Kara pulled her knee up and rested her elbow on it, dropping her chin onto her hand as she looked up at Alex. "Thank you," she said, "You know, for more than just the waffles."

"I've got your back, always," Alex said with a smile. "You're my family."

"Yeah," Kara began and gently, carefully squeezed Alex's hand. "You're mine, too." She smiled at her sister. "And I'm really thankful for it."