03/01/2016 02:47 EST | Updated 03/02/2017 05:12 EST

Why Are Some Siblings So Hateful Towards Each Other?

Siblings can be our best friends or our worst enemies. I've heard of one sibling giving up a kidney for another; being a surrogate for another one's pregnancy, or giving another sibling the down-payment for a house. So what makes one sibling loving and the other hurtful? Mostly, it comes down to what happened during childhood.

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Siblings can be our best friends or our worst enemies. I've heard of one sibling giving up a kidney for another; being a surrogate for another one's pregnancy, or giving another sibling the down-payment for a house.

I've also heard of one sibling sabotaging another sibling's career or love-life; stealing the others' inheritance, or undermining the other sibling's sense of self-worth.

Siblings can be there for us when we need them, or they can brutally abuse us. We can count on them completely, or live in fear of their hostile intentions.

So what makes one sibling loving and the other hurtful? Mostly, it comes down to what happened during childhood.

The events of childhood, whether positive or negative, have a direct effect on how adult siblings end up relating to one-another. Here are some real-life examples of troubled sibling relationships:*

Elaina grew up with parents who were extremely abusive and neglectful of the children, including their habit of locking all the food away from the children at the end of each day.

Today, one of Elaina's siblings, a successful entrepreneur with many contacts, has made it a point to distance Elaina from the sibling's colleagues, so that Elaina can never benefit from this vast business network.

Another of Elaina's siblings stole family heirlooms that had been bequeathed to her, and a third sibling only reaches out when they want something from Elaina.

As children, with so little love (or food) to go around, it was easy for the children to see their siblings as competitors for the scant resources they all so desperately needed. It's not surprising that today, most of them still feel the need to compete.

Leslie grew up with several siblings. Home life was chaotic, with a lot of parental acting out. As adults, Leslie's siblings chose to forget about the bad events in their childhood.

Leslie remembered the truth of what had happened and spoke to her siblings about how her childhood experiences had affected her, and why she'd chosen to distance herself from her parents.

Her siblings were invested in remembering a very different, whitewashed version of their early family life, and they were uncomfortable when Leslie spoke about the dysfunction they all lived through. They became angry at her choice to stop seeing their parents.

As adults, the other siblings began to ostracize Leslie from their family events. Now, Leslie has almost no relationship with any of her siblings, who continue to spend time with their abusive parents.

In Leslie's family, all of the siblings experienced trauma, but none except Leslie were able to face what had happened. As a result, it was threatening for the others to hear Leslie speak of her experiences, and it was intolerable to witness her giving their parents consequences for actions they couldn't acknowledge.

The need to bury the past made Leslie's siblings reject her, when all she wanted was a loving connection with them.

Patsy had two siblings, one of whom had always been jealous of her, as they believed that she received more attention from their parents when they were growing up. In fact, no-one got much attention during childhood, but it was easier for her sibling to blame Patsy than to face the truth about their parents.

When the wills were being made, the jealous sibling managed to make themselves the executor, and when the second parent passed away, this sibling figured out how to steal Patsy's share of the inheritance for themselves.

It's likely that because this sibling had spent their life feeling deprived of attention and nurturing from their parents, they felt the need to compensate for what was missing by trying to get more money from their parents' estate.

Sadly, stealing a sibling's inheritance won't help an adult child of a dysfunctional family feel better, because what they need and have always needed is love.

And even more sadly, being disconnected and at odds only serves to deprive both Patsy and her sibling of much-needed peer support.

Adult children often find it hard to feel anger toward their parents. They feel guilty about seeing them in a negative light, and they often harbour unconscious hopes that they might still be able to get something positive from Mom or Dad, even as adults.

Adult siblings are much more likely to act out toward each-other all the hurt, anger and frustration that really should be directed toward their parents. Instead of being there for their siblings, they become alienated, adversarial or estranged.

If you recognize yourself in one of the above situations, and are suffering the loss of sibling love and support, don't blame yourself.

If you think that you can mend the fences between yourself and your sibling(s), by all means give it a try, but sometimes, the wounding events of childhood make it impossible for siblings to have a positive relationship as adults.

The thing that keeps a family together is love, and parental love during childhood creates a familial bond that becomes the glue holding siblings together in adulthood.

It's really unfortunate that siblings who lacked parental love during childhood, and who therefore need familial love all the more in adulthood, often end up separated from each-other, even hostile to one-another.

If you've tried repeatedly to reconcile with your difficult siblings and they aren't willing to be close to you, you'll need to face and accept this tragic side-effect of a dysfunctional upbringing and look for sisters and brothers in your circle of adult friends.

The wounding events of childhood linger long into adult life, causing pain and suffering in a myriad of ways, including in the interactions of adult siblings.

Psychotherapy or counseling can help an individual heal from a difficult or painful childhood, but it can't necessarily make one's siblings more amenable to getting along.

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*The names and identifying details of all the above individuals have been changed to protect their privacy.

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