2 Kings 1:17
So he died according to the word of the LORD which Elijah had spoken. And Jehoram reigned in his stead in the second year of Jehoram the son of Jehoshaphat king of Judah; because he had no son.
Nave's Topical Index—AKJV

2 Kings 3:1
Now Jehoram the son of Ahab began to reign over Israel in Samaria the eighteenth year of Jehoshaphat king of Judah, and reigned twelve years.
Nave's Topical Index—AKJV