Can a foster child sue a biological parent for sexual abuse?

Parental immunity is a doctrine that prevents a minor from suing his or her parents for personal injury. This old doctrine has been completely abrogated by many states or very limited in others.

In a recent article  Daniel Pollack, a professor at the School of Social Work, Yeshiva University, in New York City looks at the case of foster children abused by their biological parents. The children were removed from their biological parents and placed in foster care. Gradually they were allowed to visit their parents. The biological father molested his children during unsupervised visits in plain sight of the mother. Can the children sue their mother for failing to adequately protecting them from personal injury?
Find out in the article.