Brachos 2:8-3:1
Brachos 2:8
A groom is exempt from reciting Shema on his wedding night but he may do so if he so chooses. Rabban Gamliel disagrees; he says that not everyone is capable of mustering up the necessary concentration. (Nowadays, the practice is for every groom to recite the Shema.)
Brachos 3:1
If a person’s close relative (parent, sibling, child or spouse) has died and is not yet buried, he is exempt from reciting Shema and Shemoneh Esrei, and from putting on tefillin (as well as from other obligations). The pallbearers who are needed to carry the casket are exempt from Shema and tefillin but others, who have come to escort the deceased out of respect, are obligated. Both groups are exempt from reciting Shemoneh Esrei.