Legal Question in Wills and Trusts in North Carolina

Did your father have a will or not?

I assume from your post there is no will because your brother's children would not have to sign anything otherwise. If they will not sign then there has to be some mechanism by which the court will appoint you or else serve the application for probate on them and if no written objections are filed the clerk will appoint you. The nieces and nephews do not have to do anything but they cannot gum up the works by not signing.

What did your father own? Does he have assets justifying probate? The clerk will be a good resource but they are not going to be a lawyer for you. If you cannot get anywhere on your own then you are going to have to contact a probate attorney who practices in the county where your father's estate is or will be pending. If nothing else, pay the lawyer just for a consult. However, it will help to have a lawyer assist you with administering the estate, especially if your nieces/nephews are being difficult about this.