A grandparents' medical consent form allows a parent or legal guardian to hand over all responsibility regarding their child's healthcare decisions. The form allows them to authorize medical treatment when you cant be contacted.There are specific medical power of attorney forms online giving consent for grandparents or other relatives to make care decisions for children. The grandparent medical consent form is a document that gives permission to a grandparent to make health care decisions on behalf of a minor child. How to fill out the Grandparent Medical Consent Form for Minors?