The Michigan appeals court says parents who are declared unfit can't prevent their children from being vaccinated against illness.
In a 3-0 decision this week, the court affirmed a decision by a Kent County judge who ordered vaccinations for four children in foster care.
The request was made by a state foster care worker who was assigned to their case.
The children's mother had objected to vaccinations on religious grounds.
But Judge Paul Denenfeld in 2015 said she had forfeited the right to make decisions for the children.