Officials say two-year-old A’millah Currie and nine-year-old Darnell Currie Junior were staying with their mother in a van parked in the Hollywood Casino garage.
The van lost heat and the mother took the children to a hospital after one had stopped breathing.
Detroit Mayor Mike Duggan says the mother had reached out to homeless advocates months before, but neither she nor officials followed up.
Duggan has ordered a full review of Detroit’s homeless services, wants the city to better publicize what shelters are available, and have workers conduct on-site visits when minors are involved.
The city is helping coordinate the Currie children’s funerals, which are being paid for by donations.