I have heard wonderful things about Blue Fish Pediatrics. They are off Manchester in Des Peres, not exactly Webster Groves, but I have friends who go there and love it.
Dr. Kristin Terrill. You will love her. You can set up an apt to meet her before you transfer. I met with her and another dr in the practice and I liked both of them. I've since seen a 3rd dr there and would recommend them all.