Answer:
You need to petition the appropriate court for appointment as guardian whether or not the parent consents to the guardianship. The court will appoint a guardian ad litem to examine the parent's situation and report back to the court. The court will require a physicians certification the parent is incompetent unless the parent is legally competent and has assented to the guardianship. The guardian will be required to file an inventory of the ward's estate and list all heirs at law who will be then be notified of the petition. Once appointed, the guardian will act under the supervision of the court and will be governed by state laws that govern fiduciaries.