Marc Lewis, Ph.D., and Isabela Granic, Ph.D., are developmental psychologists as well as the parents of twins. Dr. Granic is a research scientist at the Hospital for Sick Children. They are authors of the book Bedtiming: The When-To Guide to Helping Your Child Sleep. Dr. Lewis is a professor in the department of human development and applied psychology at the University of Toronto.
Together, they have been guests on international public radio programs, spoken at international academic conferences and given educational seminars and workshops to parents and clinicians around the world. Lewis, Granic and their children live in Toronto.
. Dr. Lewis is a professor in the department of human development and applied psychology at the University of Toronto. 
