Who is…
Hiel

Hebrew: חִיאֵל —transliteration: Chiel —meaning: “brother of god,” “the divine brother (or kinsman),” or “life of god” (i.e., from god)

This man was a native of Bethel, and referred to as a Bethelite. He rebuilt (i.e., fortified) the city of Jericho some 700 years after its destruction by the Israelites

For this act, he experienced the curse pronounced long before for raising up Jericho.

The curse

Then Joshua charged them at that time, saying, “Cursed be the man before the Lord who rises up and builds this city Jericho; he shall lay its foundation with his firstborn, and with his youngest he shall set up its gates.” —Joshua 6:26 NKJV

Its fulfillment

…Hiel of Bethel built Jericho. He laid its foundation with Abiram his firstborn, and with his youngest son Segub he set up its gates, according to the word of the Lord, which He had spoken through Joshua the son of Nun. —1 Kings 16:34 NKJV excerpt

This means either that during the progress of the work all his children died, or that he was an idolater and practiced (or victimized by) foundation sacrifice rituals (see the loathsome practices of idolatry).

The deaths took place during the highly heathen times of the fanatical idolaters King Ahab and his wife Jezebel, so there is reason to suspect the cause to be the later.