Harmon told KPRC that the victim was an acquaintance of the girl's father who came to the barn near Shiner, a town about 130 miles west of Houston, on Saturday to help care for some horses.
The adults were shoeing a horse and had sent the 4-year-old and her brother to feed chickens when the attack occurred, a relative told KPRC.
The children's grandfather said the boy returned to alert his father that the little girl had been taken away by a man. The father found the pair partially naked, investigators told KPRC.