Due to serious illness I need to nominate a next of kin in case of medical decisions. I have no close living relatives. I do have a very distant relative abroad who I have met once as a child. My oldest friend is named as a beneficiary and executor of my will and as next of kin in my hospital records. I do not want a relative I don't know to make decisions about my care eg if I end up in a coma. How can I make absolutely sure my friend is the one to make these decisions?