It is forbidden to extend to a mourner a greeting of "Shalom," and a mourner may similarly not extend such a greeting to others. During the first three days of mourning, if a person extended a greeting to a mourner, he must inform the person of his status. After the third day, although the prohibition still applies, a mourner may respond if somebody mistakenly extended to him a greeting. After the seven-day Shiba period of mourning, the mourner may initiate greetings to others, but people should not extend a greeting to him, until after the thirty-day Sheloshim period. In the case of somebody who lost his father or mother, this prohibition applies for twelve months after the passing.
Some people follow a stringency not to extend greetings to each other in the house of mourning, though common practice does not follow this stringency.
If, during the twelve months of mourning after a parent’s death, the mourner has a baby boy, the prohibition against extending greetings no longer applies. It is permissible to extend greetings to the mourner from that point henceforth.
This prohibition applies only to greetings with the word "Shalom." It is permissible to extend other greetings, such as "Good morning," "All the best," "Tiheyu Beri’im" ("Good health"), "Haim Arukim" ("Long life"), and so on. It is also permissible to wish "Mazal Tov" for a happy occasion of "Refu’a Shelema" ("Get well soon") in the case of illness. On Shabbat, it is permissible to extend the greeting of "Shabbat Shalom." One may extend the customary "Shalom Alechem" greeting to a mourner after Birkat Ha’lebana.
It is forbidden for mourners to indulge in casual conversation during the seven days of mourning. It goes without saying that one may not engage in lighthearted conversation and joking in a house of mourning. It is proper to refrain from excessive conversation even during the thirty-day Sheloshim period, and during the twelve-month mourning period after the death of a parent.
It is forbidden to give a gift to a mourner during the twelve months of mourning for a parent, unless the mourner is poor, in which case gifts have the status of Sedaka (charity) and are therefore permitted. A husband may buy gifts for his wife for the holidays during her year of mourning for a parent, and it is permissible to send a mourner Mishlo’ah Manot on Purim. If somebody becomes bar misva or gets married during the twelve months of mourning after a parent’s death, one may buy him or her a present in honor of the occasion. Similarly, a bride and groom may exchange gifts with one another before their wedding even if one of them is within the twelve-month mourning period.
(Based on Rav Shemuel Pinhasi’s "Haim Va’hesed")
Summary: It is forbidden to extend a greeting of "Shalom" to a mourner throughout the morning period, including the twelve-month period after a parent’s death. The mourner, however, may extend such a greeting to others after the seven-day Shiba period. Other greetings are permissible, but a mourner should not engage excessively in conversation, and joking is forbidden in a house of mourning. One should not send a gift to a mourner throughout the mourning period, except on special occasions, such as for a bar misva, wedding, holiday and the like.
