In 2006, we observed two female Texas horned lizards (Phrynosoma cornutum) digging nests in hard caliche soil in Randall County, Texas. One female used her head in a twisting and side-to-side motion to backfill the nest, which may pack soil between eggs without injuring the eggs and prevent collapse of the nest during extreme precipitation. Hatchlings emerged from nests through single holes, which coincided with original entrances of tunnels that were excavated by females, and hatchlings had left the nest ≤24 h of when the first hatchling emerged. Behaviors during their first weeks above ground changed from an instant-flee response to a sudden-prolonged immobility within ca. 2 weeks. Hatchlings ate only ants <4 mm in length and avoided larger harvester ants (Pogonomyrmex rugosus). Hatchlings shed their skin ca. 4 weeks after emergence and began hibernation ca. 6 weeks later than adults.