I'll assume for purposes of this question that you were given custody by the family court. I'll also assume that the other parent has some form of custody rights or, at a minimum, visitation rights. Based on those assumptions and absent the other parent's consent, you would need the court's permission before leaving the state.
THESE COMMENTS ARE NOT LEGAL ADVICE. They are provided for informational purposes only. Actual legal advice can only be provided after consultation by an attorney licensed in your jurisdiction. Answering this question does not create an attorney-client relationship or otherwise require further consultation.