5 year old grandson gets mild frontal headaches children's tylenol (acetaminophen) takes care of it his mom is a long time sufferer of migraines, your thoughts?

Child's headaches: I would not jump right to migraines in his age group. There are so may things that are ahead of that on the list of possible causes. First is a good eye exam from a pediatric eye doctor. Next is a general physical exam and history from his pediatrician. While you are waiting for all that to happen, keep a detailed diary of his headaches. Day, time of day, what he was doing , diet, what helped, etc.