What if a disabled student becomes incapacitated?

When a child goes off to college, many parents take proactive measures to ensure they can speak for their child if they experience an incapacitating event. One of these measures is to create an “advanced healthcare directive,” which is a legal document that outlines one's preferences for medical treatment if one becomes unable to communicate or make decisions due to illness or incapacity. It also features a healthcare proxy, which is a legal document naming a trusted person (agent) to make medical decisions on one's behalf.