1,347. Exchanging Greetings
210:7 Since the mourner is not permitted to exchange greetings, it goes without saying that he may not engage in laughter. Therefore, the entire week of shiva, the mourner may not hold a child in his arms so that he shouldn't come to laughter. Similarly, the mourner is not permitted to engage in excessive conversation with others. However, if his intention is to honor a large group, such as if many people came to console him, he may do so because honoring a group is permitted.
210:8 In a place where the practice is to greet mourners on Shabbos, one may do so. A mourner may greet everyone on Shabbos because there is no public mourning on Shabbos.