Michaela's favorite quote was: "Be the change you wish to see in the world."
Watch this tribute to the lives of Jennifer, Hayley and Michaela.
At his family's memorial service, Dr. Petit says he had a strong need to speak for Jennifer, Hayley and Michaela. "If there's anything to be gained from the senseless deaths of my beautiful family, it's for us to all go forward," he said. "Help a neighbor, fight for a cause, love your family."