Your child has just turned 18. He/she has just graduated high school and is probably off to college in the fall. Your child will always be your baby but in the eyes of the law, your child is now an adult.
This means that your child needs all of the estate planning documents that you do. Although you had the automatic right to make health care decisions for your son/daughter, you do not have that right now. Now your child needs his/her own health care proxy and living will. You do not have the right to see his/her medical records either. Before your daughter goes off to college, make sure that you have him/her sign a document called a “HIPAA Release” (named after the law that created a right to privacy about your medical records) that gives you the right to view her medical records.
Your son will also need a durable power of attorney that names you as his agent to act in connection with his financial affairs in the event he can’t. If he is in an accident and cannot speak or sign his name, the durable power of attorney will allow you to do his banking for him and make decisions for him until he can do so for himself.
Although it may seem strange to have a child make a Will, it may be necessary if that child has significant assets (maybe an inheritance from Grandma) and there are family issues. Without a will, unless your child is married, both parents inherit from their children.
Finally, since your child has reached the age of majority, he/she can act as a guardian to your younger children, if necessary. I’m not sure you want to give that kind of responsibility to a person who you barely wanted to give the car keys to just a year ago, but it can be a temporary solution to the guardian issue if you do not have another adult to whom you want to act in that capacity for your other children.