Bingowings said:
Luke is strong with the Force because (according to Lucas) the Force runs strong in his family.
This make Leia as (if not more) potentially ripe for turning to the dark side as Luke is, something Vader threatens to do which acts as the trigger for Luke to go ape on his dad (never a Captain Obvious around when you need one).
Your attempts to summon me will never.....aww crap.