As parents we relish and dread September.
The back-to-school week is fraught with tears and stress and joy. We feel guilty, but relieved leaving kids at the school gate.
All very normal, so none of us has the slightest idea about how to respond to the utter tragedy that occurred to the Hawe family in Cavan.
Two teachers, three beautiful boys, a lovely home, a close-knit community.
A perfect - some might say idyllic - life.
Five people due back at school this week are gone, murdered by a man who lived this seemingly perfect life right up to Sunday afternoon before taking their lives, and then his own.
We will never know what possessed him to murder the family he loved and cherished, as we all do our own.
Despite investigations - forensic, police and medical - we will not know the full details of what happened.
We may discover the grim and bloody facts, but we will not know the switch, trigger or moment of madness that made this family man, this respected member of the community, become a killer.
We will, in time, blame an illness perhaps, or some other factor that will allow us abstract the thought; give us the comfort we as flawed humans need to believe we could never be capable of this terrible act.
We will almost be relieved if we hear about, for instance, a gambling problem, an alcohol or drug addiction, or a huge debt that had overwhelmed this father.
We will reassure ourselves that is "them" and not ever "us".
We may never know, of course. None of these things might surface and there may be no reason that we can pin down. That is more frightening for the rest of us because then we cannot believe that it could happen to anyone.
Murder-suicide, as it is called, has occurred 30 times since 2000. Over 20 cases involved children.
John Butler from Ballycotton killed Zoe (6) and two-year-old Ella in November 2010 before taking his own life.
In April 2007, Adrian Dunne (30) from Monageer, Wexford strangled his wife Ciara (24) and his daughters Leanne (5) and Shania (3), before taking his own life.
Wexford father Diarmuid Flood (41) smothered his two children and shot his wife dead.
All were reported as suffering from depression.
Thousands of people suffer from depression however, and could never, ever do take such horrific actions.
In 2013, Martin McCarthy took Clarissa (3) into shallow waters off the West Cork coast and drowned them both. Sanjeev Chada killed his sons (ages five and ten)the same year, leaving the bodies in the boot of his car.
There are calls for more robust mental health services - for resources, money, training to be put in.
This is all as it should be and yet we still know it may not make the slightest difference in the end because we can never understand every human mind.