I know this has been added already, I just wanted to chime in with my experiences.
I have two sims with the family oriented trait (mother and daughter). It has been several weeks - conservative estimate is 5 weeks of game time - since Husband/Dad died. Both of then are continiously interupting things I have instructed them to do to go out to the backyard and cry at his grave. This mostly happens when I have instructed them to cook. EVERY time I have instructed them to cook. Instructing either of them to cook goes: Tell sim to cook > sim gets out cutting board/bowl/whatever and places it on the counter > stops all cooking and goes to the backyard to cry > is now sad for 2 hours > I send them back to finish cooking the meal > Sim returns and begins stirring/cutting/whatever the food > Sim stops cooking and goes out to the backyard to cry refreshing the 2 hour sad moodlet > I send them back to finish cooking > sim returns and progresses with cooking to the point of placing the food on/in the oven > Sim goes outside to cry at the grave, moodlet is refreshed > I send them back to finish cooking the meal (by now I am swearing because there are other sims in this household that also need tending and this has long since stopped being cute/amusing/sweet/whatever and is now just REALLY annoying) > Sim returns and MAY actually complete the meal this time, more often the mourning and sending them back routine is repeated at least once more.
This is not fun, cute, adorable, sweet, interesting, entertaining, or anything else it was intended to be. It is ridiculous and the exact opposite of "Smart". Grieving is good, grieving is wonderful and for a time I can even see this behaviour being appropriate, but when none of them even notice the sim they are mourning dying in the first place, this behaviour weeks later this is just broken.