Case details in brief.

Mrs. Chowdhury is an US citizen, filed a petition in f4 category to bring her siblings, the application got approved 8 years ago.
Last year Mrs. Chowdhury has got cancer and she was in stage 4, fatal condition. The brother and sister whom she filed a petition for they came here in the USA to see her and be with the family in this bad situation. They came here as a visitor with B1/B2 visa, they are still in USA with legal and valid status.
Unfortunately, in the meanwhile, Mrs. Chowdhury passed away. And her siblings are in the USA.
Mrs. Chowdhury has three young kinds; oldest one is 6 years, middle 4 year, and the youngest one in only 14 months. The beneficiaries, I mean her brothers and sisters are staying with the kids and other family members. The beneficiary’s father also lives in USA. They all are living in one family.
1. Is the petition that Mrs. Chowdhury filed for her brother and sister got revoked?
2. Is there any way for the beneficiaries to stay here in USA legally?
3. What is Humanitarian Reinstatement?
4. What is adjustment of status?

What do you suggest? What is your opinion?
I will be waiting for your wise decision.

1. Generally speaking, the petition ends with the death of the petitioner. In this case, the priority dates were not even current yet. The I-130 isn't revoked, but the I-485, application for adjustment of status generally cannot continue, as the I-864 cannot be included with the AOS. See INA section 204(I) relief for surviving relatives.

2. Yes, but it depends on what else they qualify for other than the pending I-130. This typically depends on their educational background and work history and a US business petitioning for them.

3. Discretionary relief on the death of the petitioner, but it doesn't sound like they would qualify, as they just entered the US.

4. See answer number 1.

You should consult with an experienced immigration attorney. Good luck.