Wis. Stat. § 701.1108: Power to treat capital gains as part of a distribution.

Unless prohibited by the will or trust instrument, a fiduciary may cause gains from the sale or exchange of estate or trust property, as determined for federal income tax purposes, to be taxed for federal income tax purposes as part of a distribution of income that has been increased by an adjustment from principal to income under s. 701.1104, of a unitrust distribution, of a fixed annuity distribution, or of a principal distribution to a beneficiary.