Wis. Stat. § 48.15
Except as provided in ss. 48.028(3) and 48.9795(2) (b) 2, nothing in this chapter deprives another court of the right to determine the legal custody of a child by habeas corpus or to determine the legal custody or guardianship of a child if the legal custody or guardianship is incidental to the determination of an action pending in that court. Except as provided in s. 48.028(3), the jurisdiction of the court assigned to exercise jurisdiction under this chapter and ch. 938 is paramount in all cases involving children alleged to come within the provisions of ss. 48.13 and 48.14 and unborn children and their expectant mothers alleged to come within the provisions of ss. 48.133 and 48.14(5).
Wis. Stat. § 48.15
This section provides that "the jurisdiction of the court assigned to exercise jurisdiction under this chapter is paramount in all cases involving children alleged to come within the provisions of ss. 48.13 and 48.14." Under this section and Rickli, 21 Wis. 2d 89 (1963), the circuit court properly stayed proceedings on a grandmother's ch. 54 [now s. 48.9795] guardianship petitions until termination of parental rights (TPR) proceedings were concluded. However, the court retained jurisdiction to do anything that did not conflict with its orders and findings in the TPR cases and once the TPR proceedings were concluded the court was free to consider the petitions. Under the facts of these cases, though, granting the ch. 54 [now s. 48.9795] petitions would have conflicted with the TPR orders. M.L.-F. v. Oneida County Department of Social Services, 2016 WI App 25, 367 Wis. 2d 697, 877 N.W.2d 401, 15-0553.