system
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human
[DC] Superman and Supergirl?

We all know how powerful Superman is, but what about Supergirl? Could she be as powerful, if not more powerful then Supes if she had been on Earth as long as him?
gpt
Not sure about the latest canon (New52/Rebirth), but story used to go that Supergirl is perhaps a tinsy bit stronger, faster etc. Their rationale was that 

A) Supergirl took a longer trip from Krypton to Earth (sent as a baby, arrived as a young adult), thus soaked up much more sunlight enroute. More energy = more power.

B) Supergirl does not have the same degree of control as Superman, who'd spent 30 some years to 'hold back' even when fighting a super robot made by Lex Luthor (or whatever). Less control/finesse = more power.