Do I have to give maaser from money that I recieved as a gift from someone who already takes maaser from their money?
Answer:
Yes. The obligation (or custom) of giving maaser depends on the person who receives the income, and not on the money.
Sources: Taz, Yoreh Deah, 331:32; Ahavas Chesed, chap. 18, in the name of Eliyahu Rabbah, Orach Chaim 156.
