They married after I was 18. Could I file I-130 for my mom.
-Yes.
Then add him when my mom file I-485?
-No. But after your mother become a green card holder or US citizen, your mother can file I-130 for your step-father. The problem is that your step-father can not legally stay in US longer enough to file I-485 if your mother is just a green card holder to sponsor him. But if your mother become a US citizen to sponsor him, his illegal stay will not afect him to file I-485 and I-485 approval.
