does a parent have a right to take there child, from a relative who has legal custody

You should hire an attorney to review the standing order in which you were granted custody. Mom may be in contempt of that order.

Even if she is not in contempt, Wisconsin does recognize the rights of grandparents and other individuals that have had a parental-type relationship with a child (such as an ex-stepparent) and you can petition the court for visitation. Your rights are found under Wisconsin Statute 767.42(1):

"... upon petition by a grandparent, greatgrandparent, stepparent or person who has maintained a relationship similar to a parent-child relationship with the child, the court may grant reasonable visitation rights to that person if the parents have notice of the hearing and if the court determines that visitation is in the best interest of the child."

If a court so orders, and the mom refuses, she would be in contempt of court and subject to further legal action.

Please get a family law attorney to take a look at that court order, and to help you understand what rights you have under Wisconsin's law.