Your mother died to save you. If there is one thing Voldemort cannot understand, it is love. Love as powerful as your mother's for you leaves it's own mark. To have been loved so deeply, even though the person who loved us is gone, will give us some protection forever.
J. K. RowlingThe fates have informed me that your examination in June will concern the Orb, and I am anxious to give you sufficient practice. Hermione snorted. "Well honestly... 'the fates have informed her'... Who sets the exam? She does!
J. K. Rowling