Chances of deportation?

My friend was taken into immigration custody 2 months ago. He's from El Salvador, has a job and pays taxes. He was not charged with anything ever- he was caught because his ex wife was like mad or something or accidentally filled something out about their son and it gave him away. He has a 5 year old son here that is a citizen, I was just wondering what his chances are to stay? he has a court date in 30 days and he seems to think he wont be sent back but I just wanna know if he's in denial or something. Does he have a chance to stay?