When the towering new Ann & Robert H. Lurie Children’s Hospital of Chicago opened its doors in June, this hands-on philanthropist stepped one foot closer to her goal: the creation of a powerhouse medical campus in Streeterville that would make Chicago a national center of medical innovation. Her $100 million donation was one of the most generous single gifts in city history. Will she give another chunk to the city? Time will tell. But all eyes are on this former pediatric nurse and her next move.

Photograph: TAYLOR CASTLE