In Abraham 1:8 we learn that children were being sacrificed to idols:
Now, at this time it was the custom of the priest of Pharaoh, the king of Egypt, to offer up upon the altar which was built in the land of Chaldea, for the offering unto these strange gods, men, women, and children.
Jeff Lindsay notes how this is also confirmed by other texts including:
Why would so many texts agree with Joseph Smith? Where did he learn this information from?