It happened to me this weekend. It was so unexpected.
Ages ago I tried to kill a sim by laughter and it proved really hard, it took sooo long. And now, just like that, because she was wearing clean clothes, watching kids TV, and the toddler made a funny face, bam! The mum of the family died.
I did however embrace the circumstances and play along
Now I have a father of 4 (kid triplets and a toddler) on his own who is only in like level 3 of his career. All of a sudden this family turned into a more challenging and unexpected experience!