^ 
it is true your family knows best if you are living with your parents. Typically a person living with their parents do not have too many possessions to worry about however after one gets married it might be a bit different.
I would hate to see my husband and/or my family fueding over what needs to be done to my body or whether or not the plug should be pulled. Or in the event that both husband and wife die at the same time…what happens to the kids and where do they go? family members often fight over custody of the kids when both parents are deceased.
Unfortunately people do fight after one’s death because everyone is so emotionally distraught. Having a living will and testament can put an end to potential family feuds.