At birth, cord blood will be collected and the infant's cries will be recorded. The infant's development will be assessed at 2 weeks and 3, 6 ½, 12, 18, and 24 months postpartum. Mothers who take selective serotonin reuptake inhibitors (SSRIs) and are breastfeeding their children will report to the study site with their children at 1 month postpartum to measure the level of SSRIs in the infant's blood. In addition, digital photographs of the infant's face, profile, hands, and torso will be taken at 2 weeks and 3, 12, and 24 months postpartum. Additional face-only photographs of the infant will be taken at these times and at birth for further in-depth analyses of facial characteristics. Mother-child interactions will be videotaped at all postpartum assessments.