Question:
how long is availus for a brother?
Answer:
Hamakom yinachem eschem btoch shar aveiliy Tzion V'yerushalayiom.
The aveilus period for all relative, except a parent, is for thirty days. The first seven days have more strict rules, and for the remaining days the rules are more relaxed. If you need help calculating it, let me know the Hebrew date of your brothers passing, and the burial.
Best wishes
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