I am in Louisiana and my brother died with no children a year before my father

Did your father have a will?

Generally an estate is divided only to surviving relatives. However, if your father willed part of his estate to your brother and never changed the will, then his heirs are probably entitled to his share of the estate.

Generally an estate is divided only to surviving relatives. However, if your father willed part of his estate to your brother and never changed the will, then [the brother's] heirs are probably entitled to his share of the estate.

Right.

But don't forget: Louisiana probate law can be very peculiar. Those of us who are from elsewhere are generally not that familiar with it.