The only way to be absolutely certain that the person(s) you want to be guardian of your minor children is selected in the event that both you and your partner pass is to have a valid will in place.
Under Michigan law, if both parents pass and a will has not been executed, a judge will decide who becomes the guardian of your children. Michigan law does not have a provision that appoints the grandparents, or an aunt or uncle, as guardian in the absence of a will. In the event that both parents pass without a will, and the entire family agrees on the appointment of a guardian, a judge will usually follow that recommendation. But, is it fair to place your extended family in a position where they have to make that decision? And, what if they don't agree? Then the only resolution is to go to court and let a judge decide.
Guarantee that your children are protected for the future with the creation of a will.