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Someone has both an Israeli family and a Gentile maid living with a U.S. family in the same house on the 8th Day of Pesach.
During the week, the Gentile has been eating her kosher chametz food in the basement kitchen away from the rest of the rest of the household. The Israelis do not have an 8th day of Pesach, however, because Shabbat immediately follows the end of Pesach, they normally would not be eating chametz in the U.S. family's home.
However, assume that the Gentile has some leftover cold chametz kosher food that belongs to her, and she offers to share her food. Is there any problem with the Israelis eating that food on that Shabbat? Can they eat it at the same table as the rest of the family, assuming that they are careful not to get chametz crumbs all over, or do they have to eat only in the chametz kitchen with the Gentile?