Wis. Stat. § 48.263: Amendment of petition.

(1) Except as provided in s. 48.255 (3), no petition, process or other proceeding may be dismissed or reversed for any error or mistake if the case and the identity of the child or expectant mother named in the petition may be readily understood by the court; and the court may order an amendment curing the defects.

(2) With reasonable notification to the interested parties and prior to the taking of a plea under s. 48.30, the petition may be amended at the discretion of the court or person who filed the petition. After the taking of a plea, the petition may be amended provided any objecting party is allowed a continuance for a reasonable time.