Siblings often serve as our first companions and lifelong competitors. They are typically the individuals we have known the longest, shaping our identities, self-perceptions, and perspectives on the world. Tonight, “Insight” delves into the profound impact of sibling relationships. Catch the episode titled “Siblings” at 8:30 p.m. or stream it on SBS On Demand.

Lea, who prefers to keep her surname private, is the youngest in her family. She reflects on how the considerable age difference between herself and her much older siblings led to complex dynamics and occasional friction.

At 21 years old, Lea describes how she felt a sense of rivalry with her brother and sister, who are 13 and seven years her senior, respectively.

“When my sister turned around 15 or 16, I remember trying hard to be a part of her world,” Lea shared with “Insight.” “I would put on makeup and try to mature more quickly just to fit into her social circle.”

Despite these efforts, Lea acknowledges that the competitive feelings were self-imposed and not reciprocated by her siblings.

“Neither my brother nor my sister saw it as a competition,” she admits. “But in my mind, I felt the need to reach their level.”

Seeing her older siblings’ successes at a young age sparked Lea’s own drive to achieve.

“[I thought] how can I almost be better, in a way, than them?” she said.

Lea’s siblings were born in Germany after their parents fled former Yugoslavia in the 1990s during the Yugoslav Wars. After the family later migrated to Australia, Lea was born.

“I think that definitely affected my upbringing and my relationship with my siblings,” Lea said.

“Living in Australia, there are so many more opportunities that you can be offered. And I think sometimes maybe my siblings saw those things as maybe I was getting more than them.”

She also thinks that by the time she was born, her parents had relaxed their parenting approach.

“I definitely think we view different versions of our parents. I think my brother definitely got the strictest version of my mum and my dad. And my sister got this nice in-between,” Lea said.

“And I got the most relaxed version, kind of could do whatever I want.”

Lea said the differences in their upbringing led to challenges.

“I think that’s what also created tension and why we became estranged for that period of time.”

Competing for parental attention

Dr Rachael Sharman, a senior lecturer and researcher in psychology at the University of the Sunshine Coast, said sibling estrangement is fairly common and often arises from rivalry or differing life stages.

“About a quarter of siblings can expect to experience estrangement at some point in their life. But … more often than not, it’s not permanent,” Sharman told Insight.

The family relationships researcher said this dynamic doesn’t always come from resentment or dislike of one another. It can be due to siblings having different personalities or being at different points in their lives.

But sometimes there is competition at play, particularly for parental attention or resources, which can be time, emotional availability and money.

“What we typically see where a sibling relationship falls apart is where there’s been quite intense competition and then some resentment that’s built up because there’s a feeling or a perception that one sibling has somehow done better than the others.

“That idea that someone has done better than someone else, that’s where we tend to see rivalry and conflict.”

‘I come from a very competitive family’

Bronwyn Frazer was the sixth child of eight in a household where competition was rife.

“If you’d put a game in front of us, it would be ‘on’ to see who could potentially outdo the next person,” she told Insight.

Though Bronwyn’s parents both worked full-time, she felt they were as fair as possible in managing the division of attention between their eight children.

“If there was any rivalry, any competition, it was more that I come from a very competitive family,” she said.

Bronwyn said that because she had so many siblings and was one of the youngest, it taught her to be a good sharer and listener.

“And I was often reminded that the world did not revolve around me, that I was one of many, and that we needed to work together.”

But she said the family dynamic and how she interacted with her siblings changed when her older brother died in his sleep in 2009.

“Of course, it shook all of us up … How it impacted me was I took on more of a responsible role for my brothers under me,” she said.

It also led her to make an important life decision — to move to the place where her brother had been living before he died.

“I realised that I was way too far away from the family.”

‘I’m always striving to be better than him’

Nineteen-year-old Charlie Jurberg and his identical twin Thomas also share a strong bond — though it’s a competitive one.

Until leaving high school, their life paths in Melbourne had been about as identical as their appearance.

“We played the same sport, were in the same friendship groups, watched the same things, played the same games,” Charlie told Insight.

“Everything we’ve done has been together, so we’ve always competed to be the best at whatever that is.”

Thomas says that while he believes he and Charlie are naturally competitive, “having a direct comparison” creates a benchmark for his standards of himself.

“Because if he does it, then I’m like: I should also be able to do it,” Thomas told Insight.

“I’m always striving to be better than him. Not because I don’t want him to succeed but because I just want to be better — or just perform to his level.”

He says that when people ask him if he has a brother, it’s difficult to answer.

“Because it’s like, yes, I do, but I view [Charlie] as just like another me — just not someone,” Thomas said.

So, when Charlie tore is ACL a few years ago and was sidelined for the sports season, Thomas saw it as a chance to differentiate himself on the local Australian rules football team the brothers both played for.

“I think it was an opportunity to prove myself and how my game is different — and that I’m actually alright,” he said.

“Even if he outperforms me in something, I view it as like ‘oh good for him’, and I always know that I can reach that mark.”

Cross-continent competition

Charlie has thought about how his and Thomas’s rivalry will evolve once they no longer live together.

“He is going to Europe through school for a while. So that’ll be a glimpse into what life would be like without him,” Charlie said.

“… But even him being on another continent, I think we’ll still be comparing and being competitive.”

Queensland-based academic Sharman highlights that sibling rivalry isn’t always a negative thing, and it can provide opportunities for mentoring and inspiring.

She notes that while the brothers constantly try to one-up each other, it is done in a “very healthy, friendly and positive way”.

“They’re actually looking at each other as a role model, not necessarily as a competitor.”

All in very different points of life

Lea says that she and her siblings chat occasionally but aren’t very close.

“We have reached a really nice balance where we chat enough times where I don’t feel disconnected from them,” she said.

Lea says that they are all in very different points of life when it comes to family, career and relationships.

“But I know if I needed something, I could always reach out, and they’d always be able to reach out to me.”

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