You, on the other hand, may be penalized for her bad behavior. You may be assessed a substantial sum of back child support, possibly all the way back to the day the child was born. The "arrears" will be applied immediately, regardless of the fact that you were unaware that you even had a child. You will also, more than likely, be labeled a "deadbeat dad" and forced to pay the back support plus interest. You should contact an attorney immediately to discuss this, and the possible future ramifications.