Just following on the question that I found the site https://dinonline.org/2016/01/18/2-sisters-marrying-2-brothers/
I once heard, that if they do, the brothers cannot live in the same city, is this true?
Before answering your question, it should be noted that such topics should be discussed in person with one’s personal Rov.
See Nitei Gavriel (Shidduchim 15 ftnt. 6), there are those that write that preferably that they shouldn’t live in the same city, but others say that as long as it isn’t in the same neighborhood, it is fine. Additionally, a big city like New York is considered like a country, and it is fine if they live in different neighborhoods, or at least in a different building.
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