Applying for Green card for parents-in-law without Birth Certificate

[SK_RT]

Hello all,
First off, thanks to everyone on the forum for sharing their invaluable experiences and suggestions. It has helped me, my wife navigate through the immigration process in the US.

My got her citizenship recently and we are planning to apply for her parents' Green card. They are both born in the 1950s and do not have their birth certificates and marriage certificate. In this case, what are our options? I have heard on this forum that an affidavit from someone elder in the family attesting their birth and marriage would be enough. They also have their 10th board certificate. My question is, will the affidavit and the board certificate be enough for them to go through the process? Can anyone share their experiences and how they obtained such affidavits? Actually what is the format of the affidavit for attesting their birth and marriage? Can someone share their template for us to use? Is a Non-availability of Birth Certificate (NABC) required?

Any suggestions, advice, tips would be super useful. Again, thank you so much for your time and attention and all the best for your journey!

[yoginishu]

One of important documents you would need is your wife birth certificate and her school leaving certificate plus school certificate which mentions both parent names and her dob. Main criteria you applying is on behalf of her relation with them. Next thing you can use is affidavit from someone and aadhar card