where did supergirl come from?

[nobfelt2]

El Mutanto reminded my of my question about Supergirl.  Well..... I was watching the original Superman movie last night and stared to think, If only 4 people survived the destruction on Krypton (Superman and the three supervillans) where did Supergirl come from ? Is she releted to superman?  Does she have a history (have human parents, go to shcool etc) or an alterego?

[mycatis]

She is supermans cousin, (I loved this film when it came out) Try looking here for info http://en.wikipedia.org/wiki/Supergirl

[Joe Shmoe]

As far as I can  remember Supergirl was Supermans' cousin who also came from Krypton. I think they may have used a bit of poetic licence to make the plot fit. It happens all the time.