Property claim after husband's death

hi my sister's husband passed away in an accident. He was merely 29 years old. My sister's in-laws are not supporting in nature and they misbehave with her. She wants to claim in the following things. please guide how to make a claim. Her husband was a government employee in bihar state electricity board. 1. A 3 BHK flat taken on home loan in the name of her husband and her father-in-law. Nominee is her father-in-law. Insurance cover is there and bank has agreed to close the loan amount and willing to give NOC. how can my sister make a claim in this property being a class 1 legal heir. She has a daughter of 13 months old. 2. LIC money in which her mother in law is nominee but her mother in law is not alive and my husband had not changed the nominee before his death. he had two Lic on his name. one of the lic was in revival period when death happened. 3. employment as a compensation, employee gratuity, pension etc. The nominee in pension is her in- laws. her mother in law is not alive only father in law is alive. please explain what an all she can claim after a government employee death being a legal heir.