House Out of Square

anng56 asks,

Our house was hit by a car that rolled into it several years ago. It knocked it out of square and our picture window on that corner leaks.  I think this was the cause because I dont remember it leaking before. The water actually runs down the wall.  There is nowhere for water to come from other than a small gap in the overhang board on the corner where it was hit.  I am starting to remodel out of my pocket slowly and would like to know the best way to deal with it being out of square.