This is a serious matter - your sister should immediately consult with an attorney and contact the child support agency attorney for your county.
Wisconsin laws do protect children when a parent has been convicted of spousal abuse:
767.41(2)(d)1. Except as provided in subd. 4., if the court finds by a preponderance of the evidence that a party has engaged in a pattern or serious incident of interspousal battery, as described under s. 940.19 or 940.20 (1m), or domestic abuse, as defined in s. 813.12 (1) (am), pars. (am), (b), and (c) do not apply and there is a rebuttable presumption that it is detrimental to the child and contrary to the best interest of the child to award joint or sole legal custody to that party.
In other words, when there has been a serious case of interspousal battery/abuse, the burden is on the person convicted of that to show the court why it should *not* give the other spouse sole custody of the child.
Hopefully your sister has an attorney helping her through the divorce - if not, she really needs one, and now. Her attorney needs to be aware of what's happened and can help straighten this out.
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