Respectfully snipped
Also, there is a community camera at the entrance. So the perp either entered via vehicle (which would be caught on camera). This camera should also confirm when CC came home (and perhaps even left).
OR,
Perp snuck thru the bushes (if any) broke in the house, murdered 3 people, took the time to write on the wall -- all while NOT knowing when dear hubby is going to come walking in. Then has to figure out an exit plan with people leaving for work, jogging, making coffee, picking up the morning paper and without a single dog making a sound as the perp leaves the neighborhood. Oh, and he HAS to miss that camera focused on the mailbox. Don't forget - never leave footprints in the grass. Oh, my bad - the neighbor mowed the lawn right in front of LE.
OR,
The perp is right in front of our face!