2 Chronicles 22:10-12

Now when Athaliah the mother of Ahaziah saw that her son was dead, she arose and destroyed all the royal family of the house of Judah. But Jehoshabeath, the daughter of the king, took Joash the son of Ahaziah and stole him away from among the king’s sons who were about to be put to death, and she put him and his nurse in a bedroom. Thus Jehoshabeath, the daughter of King Jehoram and wife of Jehoiada the priest, because she was a sister of Ahaziah, hid him from Athaliah, so that she did not put him to death. And he remained with them six years, hidden in the house of God, while Athaliah reigned over the land.