Charles Ellicott Commentary 1 Kings 22:26

"And the king of Israel said, Take Micaiah, and carry him back unto Amon the governor of the city, and to Joash the king`s son;" — 1 Kings 22:26 (ASV)

Joash the king’s son, of whom we subsequently know nothing, is apparently entrusted (like the seventy sons of 2 Kings 10:1) to the charge of the governor of the city, perhaps in theory left in command of Samaria with him.