Legal Question in Wills and Trusts in Tennessee

First question, did she have a will? If yes, then the person named in the will should consider whether to open a probate estate. If there's no will, then she died "intestate" so the three children will have first preference in serving as Personal Representative. You've not indicated whether there are assets from which the creditors can be paid. The creditors have priority over distribution to heirs. All of her children will be in equal footing without regard to who was the father.

Estates are often complicated. In the situation where you have two families, it often becomes more complicated. My recommendation, try to get a consultation with an attorney in your area that assists in the estate administration process.

Hope this perspective helps.