- Interviews: Sampled WIC participants will be recruited and assigned to either a core or supplemental group. We will interview the core group up to thirteen times over a three-year period, with a prenatal interview (for those enrolled prenatally) and interviews every two months from the child's birth through age one, and about every three months between ages 1 and 2, and every 6 months between ages 2 and 3 (at ages 1, 3, 5, 7, 9, 11, 13, 15, 18, 24, 30 and 36 months). The supplemental group will only participate in four interviews (at ages 1 or 3, 7, 13, and 24 months). Study participants will also be asked at each interview about their child's food intake in the previous 24 hours using the USDA Automated Multiple Pass Method (AMPM) and supporting materials; and a 10 percent subsample of the core group will be asked to report a second day of intake 7-10 days after the initial interviews at 13, 15, 18, 24 and 36 months. The interviews will be conducted over the phone using a Computer-Assisted Telephone Interview (CATI).