It's a story that stops you in your tracks: an entire family of four, including two infants: gone.

Earlier this week 43-year-old Scott Jones strangled his wife, Mei, then slashed the throats of their one-year-old twin sons, according to police.

While the kind of crime scene discovered in Arlington this week is rare, it happens often enough that a term has been coined to describe it: "family annihilation", when a member of a family kills everyone else and usually takes his own life.  

A recent study out of the UK finds the number one trigger is a family on the brink of breaking up, and according to several reports, that’s exactly what was going on in the Jones household.