Can my daughter take her kids out of state?

You give no indication where there is. If this is an Illinois case, and there is a joint custody order, there are two steps she must take before she can leave this state. First of all, the judgment requires that she mediate any disputes with the father. She must send him a letter requesting mediation to discuss her location by certified mail. If they are unable to reach an agreement then she must seek a court order allowing her to leave the state with the kids., If he already lives out of state, it should not be so hard to obtain from a court.