Legal Question in Family Law in Washington

Does someone else have legal custody of her? If so, follow what the order (or parenting plan) says on the subject. If the subject is not addressed in the order then, unless there is some other thing that prevents you from doing so, there should be no problem. You of course would have to return her to the custodian at the right time. If there is no legal custody order in place, there should be no problem. But there may be other things you haven't stated that could affect the answer here.