Participation in a Brother's Wedding During the Year of Mourning for the Mother

A groom getting married within the year of his mother's passing, can his brothers participate in the wedding as usual?

The brothers and sisters of the groom and bride, within the twelve months of mourning, can be present at the wedding if their absence would cause great distress to the groom. They can only be present if they serve a little at the beginning of the wedding, such as serving food or welcoming guests and seating them. They may wear Shabbat clothes, but not Yom Tov or special clothes. They should not dance at the wedding.

In the responsa of the Maharshal, Yoreh De'ah section, sign 212, it is written regarding the participation of brothers within the year: "We learn that brothers are permitted to enter the chuppah of their brother within the year, as there are no closer relatives than them, and it would cause distress to the groom if they do not participate in his chuppah. And it is clear that if we set aside the mitzvah of Sukkot so that the groom is not distressed, then mourning for twelve months, which is the lightest of the light, all the more so." And there it is explained that even according to the opinion of the Raavad, who is stringent and holds that only at the wedding of an orphan and orphaness is it permitted, this refers to the wedding of a non-Jew who is not part of the chuppah, but for brothers who are part of the chuppah, it is permitted. And there it permits even within thirty days, and so it is written in the responsa of Sha'alat Yaavetz (part 2, sign 179). The Rema wrote in sign 391: "In a mitzvah gathering, such as marrying an orphan and orphaness for the sake of Heaven, if not eating there would cancel the action, it is permitted after thirty days, but within thirty days it is forbidden for any mitzvah meal in the world (Tur in the name of the Raavad)." And in the Aruch HaShulchan it is written: "And it seems to me that it is not necessarily that the engagement would be completely canceled, but that the heart of the groom and bride would be distressed." However, since many Ashkenazi Jews are stringent in this and do not permit participation even in the wedding of their relatives, the opinion of our teacher, the Rabbi, is that they can participate in the wedding by serving, and this is because it is explained in the Rema in the name of the Kol Bo that it is permitted for a mourner to eat at a wedding meal or circumcision with the servers, provided that it is not in a place of joy, such as in another house, and the Hagahot Ashri prohibits and the custom prohibits, and he can serve and eat at his home, however, the Raak Eiger wrote in the name of the Beit Lechem Yehuda: "And in the BLY it is written that the custom in Poland is that the groomsmen also go to eat, but first serve a little." Thus, it is permitted even if they serve a little at the beginning of the meal as groomsmen. However, there is no permission to dance, as this is true joy, and being a waiter only permits eating. And what is written that they should wear Shabbat clothes, and not Yom Tov clothes, is as written in the Pitchei Teshuva, sign 389, section 3.