Family law does not discern the immigration status of a parent. Both stand equally before a family court judge in the quest for custody/visitation. So parental rights are equal and equally enforced as long as the custodial/non-custodial split is maintained for child support award purposes where the state gets a matching fund from the U.S. Treasury.
However, getting to a family court judge may be another story. The illegal alien may be precluded from entry into this country and cannot enforce his rights to his child. So, the child will grow up at the whim of the custodial parent and will be subject to abuse and neglect as doled out by that parent.
If the child is not thoroughly alienated from the alien parent, at 21 the child can petition for family based immigration of the alien parent, but the likelihood of that is extremely slim.
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