If she's lucky, the children may not be taken away and put in foster care, but the possibility that she will not have any contact with the children besides supervised visitation is a distinct possibility.
"Hi. We're from the government. We're here to help you."
Cordially,
Oh, and her hunger strike? Well, if she hasn't told jail personnel that she's on a hunger strike, they can read it here. And what do they do to prisoners on hunger strikes? Well, what they do is to commit the person to the nearest public mental health facility, stick an NG tube down her nose and force feed that person. If the person fights, they put the person in four-point restraints.
Concealing the children is another not-so-bright idea. That gives CPS an opening to petition the court for an emergency order for custody of the children, and once the children are located, one or both parents are going to be charged criminally with interference with custody (because CPS now has custody)--a class C felony under Wisconsin law (maximum sentence: 15 years in prison, $10,000 fine or both).
She's digging a deeper hole for herself.