After a century of life an oak tree buckled at exactly the wrong place and time, killing 5-year-old Nicholas Kirby and seriously injuring his father, Michael.
Typically, we worry about trees failing because of rain or disease. But, there is another reason and may have been given plenty of warning.
"Pretty thoroughly rotted; I mean the wood just crumbles in here," horticulturist Steven Swain said,
Swain is a tree expert for the University of California. He found significant decay in almost every tree on Bennett Valley Road, damage from cars and equipment hitting them through the years.
"Any of them could be in danger of falling down, someone should take a peak and see how much decay is in there," Swain said.
One complication in the story is that we may never know what happened to the tree that fell on Tuesday.
"The relevant portion, the portion that severed from the trunk of the tree, we have preserved that and we are conducting an investigation," Sonoma County spokesperson Jim Toomey said.
No matter what it finds, Sonoma County faces possible liability for the accident, because the tree fell from a right of way.
"The standard is negligence, negligence means that they knew or should have known that there was a dangerous condition, if that's true, then they could be held liable," ABC7 legal analyst Dean Johnson said.