"One takeaway from this for a parent is that our kindness and proper treatment of our children protects them to some extent because it shows them how they deserve to be treated."

YES! 1000% It's not enough for a parent simply not to be violent, nasty, or controlling with their child. A parent absolutely needs to have their own emotions and communication skills under healthy control. Otherwise, they inadvertently train their child to take the blame for others' meltdowns and to believe they're accidentally at fault for the emotional upsets of anyone the child grows up to care about.