For a father's sin

Today I was doing some research on a totally unrelated question and came across a story in the Bible I had never read before. It was 1 Kings 14 the story of Abijah's death for Jeroboam's (his father's) sin. While researching what traditional Christians would say about this I found this from 1 Kings 14:

"Arise therefore, go to your own house. When your feet enter the city, the child shall die. And all Israel shall mourn for him and bury him, for he is the only one of Jeroboam who shall come to the grave, because in him there is found something good toward the Lord God of Israel in the house of Jeroboam. "

This is the above link's explanation:

When your feet enter the city, the child shall die: Jeroboam sent his wife to discover the fate of his son. The bad news was that the child would die. Yet his death would be a demonstration of mercy, because at least he would be buried in honor and properly mourned. Such great judgment was coming upon the house of Jeroboam that all would see that by comparison, this son was blessed in his death.

Can I say first of all, I have read the Bible all the way through more than once and I don't remember this story? Can I also say that I am appalled at this thinking? There was good in him but because of who his father was he was to die and be buried and that was MERCIFUL? How about not judging him because of who his father was?

I remember the story of David and Bathsheba's 1st son dying and I remember the story of the 10th plague and I remember the story about the virgin's being parceled out to the victors while their families were slaughtered. But I missed this one and it shocked me all anew. Why can anyone say that I should worship a god that would kill a GOOD child because of his father?

It boggles the mind!