Oh my gosh I was just trying to post about this exact thing. My toddler has a +3 for two days sad moodlet about the grandmother that he never even met?!?! Do toddlers understand the concept of death?! It would really help if the sadness was appropriate to the level of relationship (Why is my Sim mourning for two days over a random work acquaintance?!) AND the age of the Sim. He's a toddler. He wouldn't be sad about Grandma dying, he'd be sad about his snack being gone because he ate it. Seriously.