Legacy's Family View displays five fields of information for the main person and their spouse. One of the default fields displays the person's Cause of Death. (See the image below.)
The person's Cause of Death will only display if you have already typed it into the Cause of Death field. This field is located in the Medical Notes. Just click on a person's Notes icon, and click on the Medical tab.
Whatever is entered in this Cause of Death field will appear in the Family View.
I've seen a lot of interesting causes of death in my ancestors' records. This ancestor's death record says he was "gored by a bull". That doesn't sound fun. Have you seen anything unique in your ancestors' records?