Maddie was diagnosed with acute lymphocytic leukemia in October 2006. Her initial chemotherapy treatment failed, so doctors developed a new plan that included more chemotherapy and a referral for a bone marrow transplant. She achieved remission in December 2006. In January 2007, no matching bone marrow donors were found, but several cord blood matches were identified. In February 2007, Maddie received a double cord blood transplant at the University of Michigan. She experienced graft-versus-host disease but tests in April 2007 showed no leukemia and full donor engraftment. Maddie continued treatment and monitoring throughout 2007 and 2008, achieving one year of remission in March 2008.