[E.G. Pediatric Aids Foundation] On a plain in Tanzania's northern region, situated between Lake Manyara and the Great Rift Valley, Yasinta sits and surveys the mountainous vista from the doorway of her boma, a traditional Maasai home, constructed of branches, mud, and dung. The middle-aged mother lives with her husband, children, and other relatives in a compound of seven bomas that sit together behind a fence of thorny bushes.