1,260. An Onen
195:14 In our countries, the practice is not to tear on chol hamoed, except for a parent, whether on the day of the burial or upon hearing of the death - even if the news was delayed. However, if the parent died on yom tov, since the tearing must be pushed off, then he doesn't tear on chol hamoed. Rather, he waits until after the last days of yom tov, when he begins his mourning period. For other relatives, we don't tear on chol hamoed; we wait after yom tov. However, if one heard of a relative's passing on chol hamoed when it's timely, and after yom tov it will be delayed, then he tears on chol hamoed. The prohibition against scratching and cutting ourselves in grief over a dead person is discussed in chapter 169.
196:1 If a person loses one of the close relatives for whom he must mourn, he becomes what's called an "onen" until after the burial. The onen should not behave in a light-headed manner so that people shouldn't say that the deceased wasn't important, which is why the onen isn't occupied with burying him and mourning him, nor is he bothered by his relative's death. To behave in this fashion would be a great disgrace to the deceased and would be considered mocking the dead. Rather, the onen should demonstrate that he is deeply affected by his relative's death and his burial. He may not eat in the same room as the deceased, but in another room. If he doesn't have another room, he should eat in a friend's house. If there's no friend's house, he should erect a partition ten handbreadths high between him and the deceased. This partition may not have a gap of more than three handbreadths between the bottom and the floor, and it must be able to withstand the wind. If the onen doesn't have anything with which to make a partition, he may turn his face away and eat. In any case, even if he's in another city, he may not have a set meal, just a snack. An onen not eat meat or drink wine.