If she gave birth to his child but they are unmarried, can she sponsor him for immigration purposes?

I know this couple that is married and still in the process of filing for the last part of the GC. However, the husband had a baby outside the marriage and the wife found out. He thinks she will revoke the petition and he will face possible deportation. As a family friend I would like to ask is it possible when she revokes the petition, can the female he had the baby with start a new petition for him to stay in the country? Due to his US born child?