My son got his illegal girlfriend pregnant (she has overstayed her visa a few years) They will be getting married soon. Will she automatically become a citizen? If not, what do they have to do so she can get on his health benefits.
If your son's soon to be spouse last entered the U.S. with inspection but is an overstay, the good news is that she should be able to file for and obtain her green card from within the U.S. based on marriage to a U.S. citizen. It is true that while most individuals who are here as overstays and/or have worked without permission are ineligible to obtain permanent resident status from within the U.S., this is not the case if you are applying for permanent resident status based on marriage to a U.S. citizen.
Addressing the last lawful entry issue, she may still pursue permanent resident status from within the U.S. based on marriage to a U.S. citizen. This is generally known as the adjustment of status process and requires filing the I-130, I-485, I-765 (work permission), I-131, I-864 affidavit of support, I-693 medical etc.
You can find info on the green card process based on marriage to a U.S. citizen at: