Hello!

My brother is getting his green card through employment sponsorship. Will his job sponsor his wife (who entered the US legally but overstayed) as well or will he have to sponsor her once he gets his papers?

Thanks for the help!

If she has overstayed, then generally she is ineligible to adjust status with her husband in the US. Her husbands company does not "sponsor" her, she is a dependent beneficiary of her husbands application.

Not enough information to advise you fully, but unless she is grandfathered for adjustment eligibility under section 245(I), she will need to have her husband petition for her. This is a much longer process. It will be 3-4 years for her priority date to be current, then she will need to leave the US and apply for the immigrant visa at her home consulate. To go to her home consulate, she must leave the US, triggering a 10-year bar. The consulate then must determine her eligibility for a waiver of that bar based on an extreme and unusual hardship to a qualifying US relative.

Get all the facts of her immigration status, any filings for her or her parents and consult with a certified immigration specialist. Complicated case, don't go pro se.