Human sacrifice was going on everywhere centuries ago for all sorts of reasons-none good-people were ignorant-and if they envied or feared you, they might leave you alone-or they might sacrifice or kill you one way or another. The druids burned people in cages-and the Spanish Inquisition tortured all non-Catholics-most to death, people in Europe and the New World burned people they called witches and heretics, etc, etc...
Pre-Christianity there were only a few cultures who said no to human sacrifice. And even they would backslide on occasion.
We are all descended from blood thirsty barbarians that did terrible things.
Hopefully we can rise above it.
Of course in this case the kid might not have been a human sacrifice. Some cultures did bury their family in the the floor of their house to keep them close. Which is kind of weird but humans are weird so what can you say?