1. That's not a good example of beat around the bush. In this situation, it seems as if your sister was being evasive. We use beat around the bush when somebody is being hesitant to do a task that they need to do. We usually say something like "Come on. Stop beating around the bush and get on with it."
2. What's the idiom here?
Next time, put the idiom that you ask about as the title of the thread. Try to stick to only one idiom per thread.

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