So Jehoshaphat reigned over Judah. He was thirty-five years old when he began to reign; he reigned twenty-five years in Jerusalem. His mother's name was Azubah daughter of Shilhi.
Ahaziah was forty-two years old when he began to reign; he reigned one year in Jerusalem. His mother's name was Athaliah, a granddaughter of Omri. He also walked in the ways of the house of Ahab, for his mother was his counselor in doing wickedly.
This verse adds a piece of information not found in the 2 Kings account. Athaliah acted as her son Ahaziah's counselor.
2 Chronicles 22:10-12:
Now when Athaliah, Ahaziah's mother, saw that her son was dead, she set about to destroy all the royal family of the house of Judah. But Jehoshabeath , the king's daughter took Joash son of Ahaziah, and stole him away from among the king's children who were about to be killed; she put him and his nurse in a bedroom. Thus Jehoshabeath , daughter of King Jehoram and wife of the priest Jehoiada--because she was a sister of Ahazaiah--hid him from Athaliah, so that she did not kill him; he remained with them six years, hidden in the house of God, while Athaliah reigned over the land.
Again, 2 Chronicles adds additional information. Jehoiada has ties to Athaliah via his wife--he is her brother-in-law. This also means that the priest is married to a descendent of Ahab.
2 Chronicles 23:12-15:
When Athaliah heard the noise of the people running and praising the king, she went into the house of the LORD to the people; and when she looked, there was the king standing by his pillar at the entrance, and the captains and the trumpeters beside the king, and all the people of the land rejoicing and blowing trumpets, and the singers with their musical instruments leading in the celebration. Athaliah tore her clothes , and cried, 'Treason! Treason!.' Then the priest Jehoiada brought out the captains who were set over the army, saying tot hem, 'Bring her out between the ranks; anyone who follows her is to be put to the sword.' For the priest said, 'Do not put her to death in the house of the LORD.' So they laid hands on her; she went into the entrance of the Horse Gate of the king's house, and there they put her to death.
Hezekiah began to reign when he was twenty-five years old; he reigned twenty-nine years in Jerusalem. His mother's name was Abijah daughter of Zechariah.
"The Scripture quotations contained herein are from the New Revised Standard Version Bible, copyright 1989, by the Division of Christian Education of the National Council of the Churches of Christ in the U.S.A, and are used by permission. All rights reserved."