2 Kings 11:2-3

2But Ahaziah’s sister Jehosheba, the daughter of King Jehoram, took Ahaziah’s infant son, Joash, and stole him away from among the rest of the king’s children, who were about to be killed. She put Joash and his nurse in a bedroom, and they hid him from Athaliah, so the child was not murdered.

3Joash remained hidden in the Temple of the Lord for six years while Athaliah ruled over the land.