Murder victim's relationship to their killer - Washington Post

Of the 12,996 homicides nationwide in 2010, about 14 percent were committed by family members. In almost half of all killings, the relationship of the slayer to the victim was unknown. Read related article.

https://www.washingtonpost.com/local/murder-victims-relationship-to-their-killer/2012/11/08/692eedde-2a01-11e2-bab2-eda299503684_graphic.html