Question: How effective is the chickenpox vaccine, and should every child get it?
Answer: The chickenpox vaccine is effective in preventing chickenpox in children who have never been exposed to chickenpox. Sometimes, even though children get the chickenpox vaccine they can still develop chickenpox -- but a much milder version of chickenpox.
Most pediatricians recommend that all children get the chickenpox vaccine if they've never had chickenpox before. And pediatricians generally recommend getting the chickenpox vaccine between 12 and 15 months of age.