Exodus 11:5

5and every firstborn in the land of Egypt shall die, from the firstborn of Pharaoh who sits on his throne, even to the firstborn of the slave girl who is abehind the handmill, and all the firstborn of the cattle.

Exodus 12:29

The Tenth Plague: Death of the Firstborn

29 bAt midnight the cLord struck down all the firstborn in the land of Egypt, dfrom the firstborn of Pharaoh who sat on his throne to the firstborn of the captive who was in the dungeon, and all the firstborn of the livestock.
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