clonecherry

Sounds like you are good to go.
 

Did you file an I-130 for each parent??  Each parent will require a separate case from start to finish.

the parents can have a visa but children of them can not
if you have other siblings,  you can apply but the wait is long 10 years or more
 
Parents could apply when they become citizens

My condolences for your loss.

Sorry for you loss. Hope you go through with this.

My father died recently while he was wating for the visa interview . NVC did not schedule an interview yet. In this case do I need to report his death and withdraw the case from the NVC? If so what is the process of withdrawing a case from NVC?  Or at the interview My mother will tell the consuler officer that my father died and provide them the proof of death.
Thank you in advance for taking the time to help me on this issue.

My father died recently while he was wating for the visa interview . NVC did not schedule an interview yet. In this case do I need to report his death and withdraw the case from the NVC? If so what is the process of withdrawing a case from NVC?  Or at the interview My mother will tell the consuler officer that my father died and provide them the proof of death.
Thank you in advance for taking the time to help me on this issue.

You could inform NVC via the online form: https://travel.state.gov/content/travel/en/us-visas/visa-information-resources/ask-nvc.html?wcmmode=disabled

if the I864 is to sponsor his father, just list him #29 1, and fill out another I-864 just for his mother

Correction, NVC requires a photocopy of the Police Certificate (and all other supporting documents you provide to them). You take the originals along with you during your interview at the embassy.