A/N: So since Kara was never stuck in the Phantom Zone, I made her be Alex's older sister but only by a couple of years.
When she was just 14 years old, Alex Danver's life was irrevocably changed. Earth's polar ice caps were melting at an alarming rate and caused most of the world to be plunged underwater, the environment was getting too hot around the world, natural resources being consumed too quickly, and the world's ecosystem was becoming very unstable. In the end though, it wasn't the Earth that exploded but the Sun.
Both of her parents were scientists who worked for the DEO and, during the last few years, had switched from their preferred fields to become environmental scientists. Eliza and Jeremiah Danvers had been working with NASA to try to create a fix for the Earth's impending doom. Eliza was working to find a suitable planet that was habitable to humans to while Jeremiah was working with others to create a new type of spaceship that was capable of traveling at light speeds and ensured the survival of the passenger by being able to withstand obstacles found in space like asteroids.
The day the Earth ended, Alex was at the DEO base with her parents. For the past few days, the Sun had been emitting huge solar flares that knocked out all forms of electronic communications, internet and cellular usage, and people were warned to stay indoors until the Sun settled down for fear of possible radiation. Scientists weren't quite sure what that meant but with a bright flash, the Sun exploded and the first waves of the massive solar flare hit Earth. The magnetic wave caused a devastating wind storm and it was only a matter of minutes before a second blast would vaporize everything in its path.
As Director Henshaw barked out orders, agents frantically scrambled around to follow protocol "S" and proceeded to get the experimental craft ready to launch. There was only one experimental craft and all the agents in the room were looking at Alex to fill the pilot seat. She had a brilliant mind and was the youngest person the room. If anyone had a chance of survival it would be her. Ignoring her protests, Jeremiah and Eliza took their daughter aside and said their goodbyes before handing her items to remember them by.
Putting on a brave face, Alex finally climbed into the spacecraft while her dad strapped her in and handed her a USB with a message that Director Henshaw had just recorded. When the timer hit zero, the ship was launched upwards and continued to ascending into the atmosphere until it left Earth's gravity field. With tears streaming down her cheeks, Alex looked out of the cockpit to see the Earth getting smaller and smaller. The last thing she saw were tendrils of fire hitting the Earth and destroying everything in it's path, as if the sun were reaching out to caress the Blue Planet. The only things Alex had left of her parents were her father's DEO badge and watch, her mother's lab coat and necklace, and a few family photos that they had in their wallets. Exhausted from crying, Alex drifted to sleep as the ship continued flying on its journey to the unknown destination.
When Alex finally woke up, she was lying in a comfy bed tucked in with a pillow under her head and she almost believed that Earth being destroyed was just a nightmare until she noticed a robot staring down at her. Giving her a few minutes to slow her racing heart and calm down, the robot known as Kelex apologized for startling her and started to inform Alex of how she ended up on planet Krypton at the House of El.
General Astra of the Kryptonian Army had been out patrolling when the pod Alex was in entered Krypton's atmosphere and started to plummet to the ground before its thrusters kicked in for a smooth landing, ending up in Astra's assigned zone. Instead of reporting her findings of the crash to the Council, Astra carried Alex to Alura's house to discuss with her twin sister what to do with the girl, Alex certainly didn't look like a threat to the planet or its people and Alura was an important member of the Council and would have good advice. Alura took Alex from Astra and tucked Alex into Kara's bed before returning to discussing with her husband and sister what to do about this human. While the Kryptonians did that, Kelex decrypted the message that was on the thumb drive and played it back to the family, shocking them with the news that Alex's whole planet was now extinct.
When Alex was finally caught up to speed and as ready for the next step as she could be, Kelex led her out of the bedroom to meet the Zor-Els, the family who decided that they would be adopting and sheltering her. The new family she'd be living with for the rest of her life. The House of El family she'd be staying with consisted of four members—Alura, Astra, Zor-El, and Kara. Alura was a Judicator on the Council and sentenced criminals to Fort Rozz or other punishments. Astra was the woman who had found and rescued Alex and she looked exactly like Alura, with the exception of a streak of white highlight in her hair. Alex could tell by Astra's stance and demeanor that she was military trained. Zor-El was a scientist and although that piqued Alex's interest, she stayed silent. Kara was Zor-El and Alura's daughter who was 16 years old (she would later discover that Kara was a huge advocate of taking Alex in). Everyone seemed kind-hearted enough but Alex wasn't ready to move on with her life yet so she closed herself off from everyone after accepting her fate. She couldn't get hurt again if she didn't let anyone in.
One month after her arrival on Krypton, the Zor-El family surprised Alex with what appeared to be a white German Shepherd puppy named Krypto. It had been Kara's idea because she wanted something to help cheer Alex up. Alex hadn't really spoken to anyone about what happened to Earth and kept all her thoughts and feeling inside so Kara suggested to get her a dog that could be her companion. Kara thought that maybe Alex could use Krypto as an outlet and talk to him when no one was around without feeling judged. Kara was correct in her assessment because within two weeks, Alex was starting to open up more and interact with her new family.
Alex spent the next several months learning to read, write, and speak the language of Krypton with help from Kara and Kelex, who acted as her tutor and translator. English really was a universal language but not all citizens of Krypton knew it and Alex had to blend in. Kryptonese was unlike any language Alex knew on Earth but she was determined to learn it so she pushed herself until she was finally almost fluent, although she still couldn't pronounce all the words correctly.
Seven months since she landed on this Alien planet, Alex had a very important decision to make that would affect her life on Krypton. Like all other children on Krypton, when Alex turned 15 she had to choose a guild to pledge herself too. Growing up and spending a lot of her time with her DEO family, Alex wanted to be part of the military guild but she also wanted to follow in her parents footsteps and continue her love for science. Alura made a convincing case for the council that Alex was smart enough to follow both paths and after a lengthy deliberation, they agreed. Alex would be dedicated to both the science and military guilds. Astra had promised to personally take Alex under her wing and teach her everything she needed to know to defend herself and Zor-El declared Alex to be his apprentice and protégée.
More months passed and Alex was excelling in both guilds. Her combat training with Astra was coming along nicely and Zor-El was an excellent mentor in teaching Alex about the sciences on Krypton. Before she knew it, a year had passed and on the anniversary of Earth's destruction, Alex reflected on what had transpired during the past 12 months She had lost everything and everyone from Earth but she also gained so much. She got a new family who loved her as if she were truly one of them and she acquired the best older sister she could imagine in Kara. One who was protective, kind and loved Alex unconditionally even before they really bonded. Alex also had Krypto who was a very loyal companion and for some reason only fully obeyed her commands. The truth was that while it was the end of the world, her world, it was also the start of a new one and she was finally ready to move forward without constantly looking back. For the first time since she had arrived on Krypton, Alex could truly say that she was home.
A/N: Thanks for reading. Feel free to leave a comment.