Highly unlikely that the mother is Ameraucana. Americauna crosses (Easter Eggers) typically have pea combs rather than single combs and the legs usually have a geenish tint to them. I think the mother is likely the Jersey Giant (if not, then it's the Barred Rock).
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The mother definitely had lots of black feathers in her, so that rules out the White Rock, Danish Brown Leghorn, and New Hampshire red.
The mother also had non-feathered yellow legs, so that rules out the Black Copper Marans, and assuming your Ameraucana is actually an Easter Egger...