Your son will have to find funds for a lawyer. If he sits on his rights he will lose them. In addition, if she is seeking benefits, he will shortly find his paycheck garnished by the state of washington to reimburse them for the child's benefits.
The first thing he must do is establish paternity through a DNA test. Admitting paternity via the the BC is just admitting , not proof. There may be surprise and maybe not. But , he needs to know now, later will be too late and he will be on the hook forever ( at this point in the law)
He can try to see if he qualifies for legal aid services . And now he has two states to deal with. I cannot preach enough to establsih everything the minute of birth.
see this article:
http://www.ajc.com/news/court-knew-man-jailed-91036.html


