This continues the prophecy about the people of Moab. God describes events that will happen in the future as if it is happening in the present. This verse is probably what God says the rulers of Moab will say to each other ([Isaiah 15:1-2](../15/01.md)).
The "daughter" of a city means the people of the city. See how you translated this in [Isaiah 1:8](../01/08.md). Alternate translation: "the people of Zion" or "the people who live in Zion" (See: [[rc://en/ta/man/jit/figs-idiom]])