If an adult becomes unable to handle day-to-day financial or medical affairs affairs, someone else must step in to take care of things. If the incapacitated person planned ahead and signed durable powers of attorney for finances and health care, the person named in those documents can take charge.
However, if no planning has been done -- a common situation -- then family members must ask a court to appoint a conservator or guardian. This person will have the court-ordered authority and responsibility to manage the incapacitated person's affairs.*
This is just one of many areas of expertise. Please contact me for more information.