Dr. Alan Greene
Dr. Alan Greene. (Tami DeSellier)

Just how bad are cold medicines for children? What are the early signs of autism? How do you quiet a colicky infant? Dr. Alan Greene is a clinical professor of pediatrics at Stanford University and the founder of parenting Web site drgreene.com. His most recent book, "Raising Baby Green," explores environmentally aware approaches to children's health. You may post your questions below. Please remember that Dr. Greene cannot answer all of them, and he cannot respond to solicitations for personal medical advice.