His career couldn’t be more different to that of his award-winning actress sister Carey Mulligan. 

While the Great Gatsby star attended glitzy red carpets and movie sets, her brother Owain has spent his career dodging bombs and bullets in war-torn countries.

After quitting his job as a teacher, Carey’s older brother, 42, decided to pursue a career in the military and became a Territorial Army soldier. 

Dealing with warring militias, keeping areas secure and the emotional toll of losing comrades, Owain served in three operational tours in Iraq and Afghanistan, despite it never being his full time job.  

And now Owain has shared an insight into his career in his upcoming memoir The Accidental Soldier as he admits that while he was flying to Afghanistan, Carey, who he has described as his ‘best friend’, was boarding Leonardo DiCaprio’s private jet. 

He wrote: ‘I remember on one of my tours I flew to Afghanistan on a trooping flight with 150 other soldiers, and all they give you is a bottle of water on board, but apart from that they sit you in your helmet and body armour for 10 hours.

Carey Mulligan’s soldier brother has had a VERY different career to the famous actress as he reveals he flew to Afghanistan while his sister boarded DiCaprio’s private jet

After quitting his job as a teacher, Carey’s older brother, 42, decided to pursue a career in the military and became a Territorial Army soldier

‘So, I was on that flight at the exact same time that Carey was crossing the Atlantic on Leonardo DiCaprio’s private jet, which always struck me as a particularly galling juxtaposition.’

Owain was stationed in Iraq for seven months after he received a TA officer training at Sandhurst and further training in Germany before being deployed with his regiment.

He thought he would be given relatively minor duties, maybe some sort of liaison job, but ended up 3rd Troop leader of B Squadron, a fighting troop stationed in Basra in 2006.

Discussing how his fellow soldiers reacted when they found out who his sister was, he joked: ‘They’d say the most outrageous things like, “Sir, how can you be out here living your life when your sister is just so much more successful?”‘

Owain, who is now a management consultant, teased over sibling rivalry: ‘Over the years there’s been a lot of jealously and bitterness, but as I say to Carey, “I’m sorry, you just can’t be a management consultant no matter how much you like it, it’s not doable for you”.’

When Owain attended Carey’s wedding to Mumford & Sons frontman Marcus Mumford in 2012, he’d only met him about four times because he’d been away with the army so much.

‘I went to the wedding the day after I got back from Afghanistan, with a haircut that had been done by an Afghan barber in Camp Bastion, for which I will never forgive him.’

He rarely attends red carpet events with his sister, but did almost appear as an extra in her film Suffragette.

Owain explained:’So, I was on that flight [to Afghanistan] at the exact same time that Carey was crossing the Atlantic on Leonardo DiCaprio’s private jet’ (Carey pictured in March) 

Owain was stationed in Iraq for seven months after he received a TA officer training at Sandhurst and further training in Germany before being deployed with his regiment.

Owain has shared an insight into his career in his upcoming memoir The Accidental Soldier

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He explained: ‘I ended up on the cutting room floor because they thought it was weird that some random policeman sitting in a cinema looked a bit too much like the lead actress.’

Joking aside, the pair are extremely close and have worked together to raise funds for War Child, which supports children in war-torn countries.

Speaking about his time in the army he added: ‘My learning curve was vertical. I’m constantly surprised that they let me go on operations as a troop leader with as little training and competence as I had at the time.

‘The army was scraping the bottom of the barrel and I was almost certainly at the bottom of that barrel.’

Back in 2014 Carey spoke of her pride after her Army captain brother helped save a girls’ school that had been targeted by the Taliban.

She revealed that Owain had set about trying to raise money to create a new well and after working with War Child, the school later reopened. 

The star said her brother’s efforts had inspired her to become an ambᴀssador for the charity, which helps youngsters in war-stricken countries.

Owain attended Carey’s wedding to Mumford & Sons frontman Marcus Mumford in 2012 (pictured 2014), he’d only met him about four times because he’d been away with the army

She told Harper’s Bazaar: ‘When my brother was a soldier in Afghanistan, he was at a base around the corner from a girls’ school that had to be shut down because of the Taliban. They had poisoned the water source. 

‘The only way it could reopen was if a new well was built. So my brother took up the initiative, amazingly, and started raising money for this school.’

She continued: ‘War Child was a charity that responded immediately. Since then, my brother has been a big fan, and when he left the Army… we met with them and started talking about working together. 

‘War Child is just extraordinary. They counsel kids through conflict and help them for years after a trauma.’

The Accidental Soldier by Owain Mulligan is available April 10.