Proof of sibling without birth certificate

[ssdesign]

Hi,
I am a US citizen and want to apply for my siblings I-130 but I do not have a birth certificate.
What options do we have to prove that my sibling is my biological brother in the absence of birth certificate of one sibling?

Any help is appreciated.

Thanks

[newacct]

Why do you not have a birth certificate? The visa reciprocity and civil documents by country page for your country of birth may list alternative documents that are acceptable in lieu of a birth certificate.

[bshachek]

I had to do it recently for my wife. I submitted an affidavit by her mother. You can submit an affidavit or better a parent OR
Affidavit by Close Relatives: close relatives (older than the applicant) who have personal knowledge of the birth can execute the affidavit. The affidavit should contain information as mentioned above.
Affidavit of Birth.

Affidavit by Parents/close relative/ other: They can execute an affidavit stating the details of the birth. The affidavit should include:

Their relationship to applicant

How well they know the applicant
.
How they came to know the facts they are swearing to

Date and place of birth

Any other related facts

Execution Before an Official: The affidavit must be executed before an official authorized to take oaths or affirmations, such as a Notary.