הלכות אבל

Although the mourning rites are not observed at all during the festival, one should rend his garments because of his dead on a festival and uncover his shoulder. Similarly, we bring the mourners bread of comfort during a festival. All of the above applies during Chol HaMoed. On a festival, even the second day of a festival, one should not rend his garments, uncover a shoulder, or bring bread of comfort.

We rend our garments and uncover our shoulders during a festival only for the relatives for whom we are obligated to mourn, for a sage, an upright person, or for a person when one was present at the time his soul expired.
Everyone brings the meal of comfort to his colleague for a sage during a festival in the main street of the city in the way the meal of comfort is brought for mourners. For everyone is a mourner because of him.

When we bring mourners the meal of comfort during a festival, we serve them while they are sitting on upright couches. We do not recite the mourning blessing during a festival. We do however stand in a line, comfort the mourners, and take leave of them.
We do not leave the bier in the public thoroughfare lest that encourage the delivery of a eulogy. For it is forbidden to deliver eulogies and to fast during a festival. Similarly, one should not gather the bones of one's father and mother during a festival for this evokes mourning for the person. Needless to say, this applies with regard to one's other relatives.
Similarly, we do not eulogize the dead on Chanukah, Purim, or Rosh Chodesh. We do, however, observe all the rites of mourning on those days. It is permitted to deliver eulogies on the days which precede and which follow Chanukah and Purim.

During a festival, the woman may lament, but they do not pound their hands together in grief. On Rosh Chodesh, Chanukah, and Purim, they may both lament and pound their hands together in grief; they may not, however, recite dirges on any of these days. Once the dead has been buried, they should neither lament, nor pound their hands together.

What is meant by lamenting? That all raise their voices in mourning together. By reciting dirges? That one recites a dirge and all respond in lament, as implied by Jeremiah 9:19: "to teach your daughters mourning and a woman, her friends, a dirge."
When do all the above restrictions apply? When ordinary people die. When, however, a Torah scholar dies, he is eulogized during a festival. Needless to say, this applies on Chanukah, Purim, and Rosh Chodesh. This does not apply on the second day of a holiday.
On the days when a eulogy is permitted, it is permitted only in the deceased's presence. Once he is buried, a eulogy is forbidden. On the day when one hears a report of his death, it is as if one is in his presence and he may be eulogized even if it is a distant report.

A woman should not have a eulogy recited for a deceased person within 30 days so that the festival will not arrive when they are grieving. For a deceased person will not be forgotten in less than 30 days. When does the above apply? With regard to a person who died previously. If, however, a person died within 30 days of a festival, a eulogy may be recited.

The seven days of the wedding celebrations are comparable to a festival. Thus if a close relative of a person - even his father or mother - dies in the middle of these days of celebration, he should complete the seven days of celebration and then observe the seven days of mourning. He also counts the 30 days of mourning from the conclusion of the days of celebration.

The following rules apply when one prepared all the necessities for the wedding feast, baked his bread, slaughtered his animals to enter the celebration, and then one of his close relatives died before he began the celebration. If he did not place the meat in water, he should sell the meat and the bread, observe the seven days of mourning, and then observe the seven days of the wedding celebrations.
If he already placed the meat in water - in which instance, it cannot be resold - the corpse is placed inside a room and the groom and the bride are taken to the wedding canopy. Afterwards, he should engage in the marital relations which are a mitzvah, and then separate from his wife. He should observe the seven days of celebration and then the seven days of mourning.
Throughout the seven days of celebration, he must observe the private aspects of the laws of mourning as is required on the Sabbath. Therefore he should sleep together with other men and his wife should sleep with other women so that they do not engage in relations. For these 30 days, the bride should not be prevented from wearing jewelry.
In a place where it is possible to sell the meat even though it was placed in water, it should be sold and the mourning period observed first. In a place where it is impossible to sell the meat even though it was not placed in water, the wedding celebrations should be observed first.
When does the above apply? When the father of the groom or the mother of the bride die. For if this feast is spoiled, they have no one to work to prepare another for them. If, however, the father of the bride, the mother of the groom, or other relatives die, one should observe the mourning period first. Only afterwards, should he enter the marriage canopy and observe the seven days of wedding celebrations.