2 Kings 1:17

17So he died according to the word of the Lord that Elijah had spoken. Jehoram became king in his place ain the second year of Jehoram the son of Jehoshaphat, king of Judah, because Ahaziah had no son.

2 Kings 8:16

Jehoram Reigns in Judah

16In the fifth year of bJoram the son of Ahab, king of Israel, when Jehoshaphat was king of Judah,
Septuagint, Syriac lack  when Jehoshaphat was king of Judah
Jehoram the son of Jehoshaphat, king of Judah, began to reign.
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