Isabela Granic, Ph.D. and Marc Lewis, Ph.D.
Isabela Granic, Ph.D., and Marc Lewis, Ph.D., are developmental psychologists in Toronto and parents of 4-year-old twins. Their book Bedtiming: The Parent’s Guide to Getting Your Child to Sleep at Just the Right Age (The Experiment) walks parents through the stages of development up to the age of 4 and reveals the windows during which sleep-training methods are most likely to succeed.