For the first 22 years of his reign, he was coregent with his stepmother and aunt, Hatshepsut. She was also pharaoh, and probably the actual ruler for the first part of his reign. During the final two years of his reign, he appointed his son and successor, Amenhotep II, as his junior co-regent. His firstborn son and heir to the throne, Amenemhat, died before Thutmose III.