Who is Power Girl?  She's the last daughter of Krypton, cousin of the Golden Age Superman.  Like him, she was rocketed from Krypton as it exploded.  However, unlike her cousin Kal-L, the trajectory of her rocketship took a different...longer...course.  As such, she spent sixty years in that craft, which her father, Zor-L, named the "Symbioship".  This ship had within it two unique devices: a suspended animation stasis field, which allowed her to age to her early twenties and kept her that way, and a mental-simulation device.  This device raised her in a dream-world based on Krypton itself.

Upon reaching Earth, she was found and instructed in the ways of the real world by Superman.  At a certain point, she broke off from his protective care, striking off on her own and becoming a renowned member of the greatest heroes of all time, the Justice Society of America!  It was with them that she met the Huntress on their first case, against the Thorn, Sportsmaster and the original Huntress.  Of all the people she met over the years, Helena Wayne was one of the few who understood...and truly appreciated her.  Thus, when Helena passed away during the Crisis on Infinite Universes, Power Girl mourned the loss of her good friend...while struggling to learn of her