An administrator may be unanimously selected by all the heirs of a deceased intestate unless the sole heir is the decedent's surviving spouse and an action for divorce or separate maintenance was pending between the deceased intestate and the surviving spouse at the time of death. With respect to any heir who is not sui juris, consent may be given by the guardian of the individual. When no such unanimous selection is made, the probate court shall make the appointment that will best serve the interests of the estate, considering the following order of preferences:
OCGA § 53-6-20