Wis. Stat. § 701.1009: Beneficiary’s consent, release, or ratification.

A trustee is not liable to a beneficiary for breach of trust if the beneficiary consented to the conduct constituting the breach, released the trustee from liability for the breach, or ratified the transaction constituting the breach, unless any of the following applies:

(1) The consent, release, or ratification of the beneficiary was induced by improper conduct of the trustee.

(2) At the time of the consent, release, or ratification, the beneficiary did not have knowledge or a reasonable opportunity to obtain knowledge of the beneficiary’s rights or of the material facts relating to the breach.