WHAT IS THE ORDER OF INHERITANCE IF A WOMAN DIES WITH OUT A WILL- HUSBAND IS GONE AND THERE ARE NO CHILDREN- THERE ARE SISTERS AND NIECES AND NEPHEWS FROM DECEASED BROTHERS AND FROM SISTERS THAT ARE STILL LIVING.
If there are no children the inheritance first goes to her father. Assuming in your case there is no father as well, the inheritance goes to the offspring of the father, firstly his sons and their offspring. So it would go to the sons of the brothers.
Bava Basra 108b, 115a, Shulchan Aruch C:M 276.