Manasseh’s father was the pious King Hezekiah. He had cleared the land of idols (see 2 Kings 18:4), but his son undid the work of Father Hezekiah. Ahab is mentioned here, as he had introduced the ten tribe kingdom to the idols of the Phoenicians (from the area of Sidon).
Manasseh did not do this just for the people or to please the desires of the nation; this was also his intrinsic choice. For, 2 Kings 21:3 explains that he himself worshipped all the host of heaven and served them. This is a new form of idol worship which had not previously occurred with the kings of Judah.
In this big difference between Hezekiah and his son Manasseh we can see that faith is not hereditary and non-transferable. Everyone is asked to make a personal choice. In short, and perhaps somewhat incomplete: God has children, but no grandchildren. That is not to deny the covenant, but it explains that a person cannot rely on his ancestry in his personal relationship with God. A person must choose for themselves.
3 For he rebuilt the high places that Hezekiah his father had destroyed, and he erected altars for Baal and made an Asherah, as Ahab king of Israel had done, and worshiped all the host of heaven and served them.