Hello and thank you for using Just Answer,If your mother is a Non US person (and never has been one) then you will not need to pay gift tax on the $120,000 she gives to you in the US.You will need to report the gift on Form 3520. You must report the gift but you will not be taxed on it.
Your mother will have no tax obligation to the US on the gift.
Because your mother in a Non US person, she is not obligated by the US gift tax laws. Yu are in that you must report the gift because it is over $100,000 but you will not have to pay tax on the gift.
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