Compare the references and notes. The author of Chronicles differs from Kings primarily in its additions (see the note on 2 Kings 21:17…

Manasseh was twelve years old when he began to reign, and he reigned fifty and five years in Jerusalem: but did that which was evil in the sigh…

Manasseh was twelve years old
From here to the end of (2 Chronicles 33:9) the same things are recorded, …

We have seen Manasseh's wickedness; here we have his repentance, and it is a memorable instance of the riches of God's pardoning mercy and the powe…