My dad just got his green card through my sibling who is a US citizen. While he was in the US visiting her, his case was denied because he did not have enough proof of his identity. So he left US immediately and appealed from India. They accepted the proofs and sent him his green card at my sister's address in the US.
Now it seems that since he got his green card, his 10 years visitor's visa would have been cancelled (from what I have heard). So how does he get his green card? My sister does not want to mail the card as there is a risk of it getting lost or stolen.
So the questions we have are:
1. Is his visitor's visa still valid or would it have been cancelled?
2. Within how much time does he have to be in the US after they issued the GC?
3. If his visitors visa has been cancelled, does he have to get a new visitors visa?
Any help would be highly appreciated.