This work was supported in part by a Doris Duke Fellowship for the Promotion of Child Well-Being, by the Washington University Institute of Clinical and Translational Sciences grants UL1 RR024992 and TL1 RR024995 from the National Center for Research Resources, and by the National Institute of Mental Health (P30 MH068579, T32 MH019960, and F31 MH098478).
The authors report no competing interests.