2 Kings 3:1

Jehoram the son of Ahab became king over Israel in Samaria in the eighteenth year of Jehoshaphat king of Judah, and reigned twelve years.

2 Kings 1:17

So Ahaziah [the son of King Ahab] died in accordance with the word of the Lord which Elijah had spoken. And because he had no son, Jehoram [his younger brother] became king [of Israel, the northern kingdom] in his place in the second year of Jehoram the son of Jehoshaphat, king of Judah [the southern kingdom].

1 Kings 22:51

Ahaziah the son of Ahab became king over Israel in Samaria in the seventeenth year of Jehoshaphat king of Judah, and he reigned over Israel for two years.

2 Kings 8:16

Now in the fifth year of Joram (Jehoram) the son of Ahab king of Israel, when Jehoshaphat was king of Judah, Jehoram the son of Jehoshaphat king of Judah became king.

Treasury of Scripture Knowledge

Summary

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.

Bible References

Jehoram

2 Kings 1:17
So Ahaziah [the son of King Ahab] died in accordance with the word of the Lord which Elijah had spoken. And because he had no son, Jehoram [his younger brother] became king [of Israel, the northern kingdom] in his place in the second year of Jehoram the son of Jehoshaphat, king of Judah [the southern kingdom].
2 Kings 8:16
Now in the fifth year of Joram (Jehoram) the son of Ahab king of Israel, when Jehoshaphat was king of Judah, Jehoram the son of Jehoshaphat king of Judah became king.