Sarah Brucker died in her Delafield condo, after it caught fire Wednesday night. She opened Blush Beauty Boutique in Milwaukee and has two young children.
State fire investigators say they have not ruled out foul play. The Waukesha County Sheriff's Office is also assisting in the probe.
The blaze was reported around 9:00 P.M. Wednesday and five alarms were sounded. Two other families escaped.
Brucker was a makeup artist. The 36-year-old recently sold her interest in the salon she had owned in Milwaukee, in order to start a beauty consulting business.