Madison Nicole Ziegler, born in Pittsburgh, Pennsylvania on September 30, 2002, is a professional dancer and actress. She was one of the stars of Lifetime's Dance Moms for six seasons, and was the lead dancer in Sia's critically acclaimed music videos "Chandelier," "Elastic Heart," and "Big Girls Cry." Maddie is a judge on So You Think You Can Dance: The Next Generation. Her first book, The Maddie Diaries was a Sunday Times bestseller.