Sister died. No will. No husband , only 1 adult son that lived with her. No assets other than house. In the state of NC.

Your nephew can provide proof of his legal ownership of the house to the mortgage company and submit a request for a loan modification. There is a standard form called a "request for assistance" that needs to be filed. I recommend that he contact a nonprofit housing agency for help. He can find one in his area by going to this web site: https://apps.hud.gov/offices/hsg/sfh/hcc/hcs.cfm?webListAction=search&searchstate=nc (copy and paste into your browser). I wish him the best of luck. He can take over the Chapter 13 Plan payment as well if the case has not yet been dismissed. He would need help from a consumer bankruptcy attorney for that. He can find a qualified one at https://www.nacba.org/find-an-attorney/ (copy and paste into your browser). I wish him the best!