2 Chronicles 36:9

9Jehoiachin was eight years old when he had begun to reign, and he reigned for three months and ten days in Jerusalem. And he did evil in the sight of the Lord.
36:9 Eight years old: He was associated by his father to the kingdom, when he was but eight years old; but after his father’s death, when he reigned alone, he was eighteen years old. 4 Kings 24.8.(Challoner)
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