Kara Zor-El claims to be the daughter of Superman's uncle Zor-El and his wife Alura. Here, Kara is actually older than Kal-El (Superman) and was a teenager when he was a baby. When Krypton exploded, she was sent in a rocket (in suspended animation) to look after Superman. However, her rocket got caught in a Kryptonian asteroid and she has just now arrived on Earth. She came to Earth essentially to look after this baby who was sent at the same time. But her rocket got wedged into a huge chunk of the planet and it has taken years to get here. When she arrives, the baby isn't a baby, he's Superman -- the greatest hero the universe has ever known. And as a teenager who has lost everything in her past, this is quite the monkey wrench. It may be part of the reason why, at least at first, she'll be hesitant to spend too much time with Superman. She was supposed to take care of him, not the other way around.
Following the end of "The Supergirl from Krypton" arc, Kara officially introduces herself to many of the heroes of the DCU, and adopts a Supergirl costume and name. Kara acknowledges that she is not even the first Supergirl, and that the other Supergirls prior to her are gone now, which troubles her. This was the new series' first acknowledgment of the Matrix/Linda Danvers incarnation of Supergirl, (confirmed as the first, original Supergirl in post-Crisis continuity) and of Cir-El as well.
Kara Zor-El is currently travelling across the DCU, learning what it means to be Supergirl as she also learns what it means to be a teenage Earth girl. She lives - as yet - on Themyscira, and has no true friends, though she has found a kindred soul in Stargirl, a crush in Nightwing, and an enemy in Lex Luthor. How all of this will affect her journey from here on out remains - as yet - to be seen.
Mun's Note 2
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