Why is it that siblings often fall out in such a bitter fashion on the death of parents? Is it a petty dispute over the will? Or is it something deeper?

For many years a given family of siblings may rally round their parents. As children and adolescents this is usually a matter of physical or economic necessity – unlike most of the animal kingdom human children take many years to fledge.
As young and middle aged adults the sibling relationship may trog along quite reasonably although at this stage tensions may start to appear as the siblings develop their own relationships and bear their own children.
The novelty of the newborn and the pleasure they give to the grandparents may heal and unify any rifts which appear in the family unity at this stage. Novelty and young children are a fine glue and many species have evolved to find attraction in the faces and gamboling antics of the young.

But as life wears on cracks appear in the sibling relationships. Cracks may also appear in the individual lives of the siblings. Their own marital relationships may be problematic. Their children will give them the normal worries of any parent. They will face career difficulties, financial problems, health scares. None of these need necessarily destroy the original family bonding.
But then the siblings’ parents age to the extent that they, the parents, reach a second childhood and become a burden rather than a support. Siblings worry and squabble over what to do about the aged and now infirm parents: will their money see them through, who will look after them, will the family home have to be sold?

By now petty jealousies and rivalries may well have developed between the siblings. One sibling may envy the life of another, the possessions, the health, the happiness or whatever. The storm clouds form.
Inevitably one sibling will play a bigger role in the care of the aged parents than the others. In a well balanced and loving family this may end well – that sibling might be praised and offered just reward for some years of sacrifice and difficulty.
In other families the eventual death of the parents leads not to a celebration of lives well lived but to a bitter and vicious squabble over the will.
A sister (one of five siblings) and her husband and children spend seven long years catering to the every need of a mother with increasingly severe dementia and an increasingly crippled and mentally frail father. There was no cash to pay them for the full time job, so they were promised reward on death.

And on the death of the last parent all hell breaks loose. Two of the siblings accuse the carer of theft – undocumented and totally spurious. The motive for the accusations remains unclear but some long seated jealousy or sibling rivalry seems certain. A third sibling gets involved in purchasing a part of the parental home while the caring family retain the other part in recompense for their effort.
And boom! Suddenly even that sibling turns on the carer when it comes to “negotiating” financial and physical details of the property division.
The original parents were not easy people. A father with lifelong depression or bi-polar disorder, a mother who struggled with insecurity, a waspish tongue and, perhaps, fear. Certainly it was not an easy life for them with five children to raise.
A life of dispute, back biting, jealousy and unpleasantness trickles down through the generations. Is it genetics or life’s circumstances? Nature or nurture? Who knows.
How glorious to be a human.