Inviting Sister/Uncle on B2 visa---urgent!!

[gauravhawk]

I am a US citizen here in USA. I am planning to invite my sister and uncle from India to visit us soon and spend some time here with us. Here I have a question:

1) I understand that in order to invite parents, I would need to show my Birth certificate to Embassy prove my relation with them. But is there any document required to prove relation with sister/brother or uncle? If yes, what kind of document.

2) one of my friend is on F-1 student visa here nd want to invite his sister and brother. He is also having the same question. What documents, if any, does he need for the same issue?

Any advise would be grateful.

Thanks,
Gaurav

[immihelp]

1.
Brother/Sister - Birth certificates of both the siblings to prove that they have the same parents.

Uncle - Lets say he is brother of your father. Your birth certificate to prove who your father is. Then, birth certificates of your father and his brother to prove that they have the same parents. That is how you prove he is your uncle.

2. Same answer.