Midrash for Chullin 99:26

כל שלשה ימים הראשונים בא ממקום קרוב מונה עמהן ממקום רחוק מונה לעצמו

is not in accordance with the View of R'Simeon B'Gamaliel in the matter of Trefah, but the halachah is in accordance with the view of R'Simeon in the matter of Mourning, for Samuel has taught: In matters of mourning the law is always in accordance with him who states the more lenient view.

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