'I knew we would all die if I didn't let go': Mother recalls agonising decision to let go of five-year-old son's hand in order to save his brother as Boxing Day tsunami hit... and how her little boy survived 

• e-mail

It was a beautiful sunny morning for the Searle family as they sat by the pool in their Phuket hotel on Boxing Day in 2004.

Jillian Searle and her two boys, from Perth, WA, were oblivious to the horror that was about to unfold as the devastating tsunami hit the popular Thai island.

Ms Searle recalls playing with Lachie, five, and Blake, two, as the first wave hit, before she was faced with a decision no mother should have to make - which of her two sons she should save.

Scroll down for video 

Jillian Searle celebrating Christmas with her two sons Lachie (front) and Blake (back) back in 2004 - just before their holiday in Thailand

Brothers Blake (left) and Lachie (right) who both survived the terrifying tsunami in Thailand's popular holiday island Phuket

The boys were holidaying with mum Jillian and dad Brad at the time of the disaster

She was getting young Blake and Lachie ready for a swim. Her husband had momentarily gone back to the room to get a spare pair of swimmers. 

'I remember hearing what sounded like jet planes so I looked up at the sky and didn't see anything so I thought that was quite weird,' she told Daily Mail Australia.

'At that point I also saw all these birds flying away and thought that was weird too.

'Then these two security guards ran past us and were on their walkie talkies which is when I looked up and saw this enormous amount of water coming towards us at a very fast pace.'

She grabbed her two-year-old and yelled at Lachie to run for his life.

'I had Blake in my arm and grabbed Lachie's hand and I never looked back,' Ms Searle said.

'I remember getting into the hotel lobby, trying to get up on the breakfast bar but it was too full.

'I was yelling for help and then I saw this teenage girl, Elise, and she put out her hand which is when I let go of Lachie because I thought he would be okay with her.

'I knew we would all die if I didn't let go of one of the boys. I just wouldn't have had anything to fight the water.' 

That was the moment she let go of Lachie, hoping he would survive, as she got pulled under the water while she held onto Blake.

'At one point I thought I was underwater forever,' Ms Searle said.

'But every now and then when I got up above the water I could hear Blake screaming - so I knew he was still alive.'

Jillian (pictured) was holding Blake (front) in her arms as she got swept up in the tsunami. She was holding Lachie's hand but had to let go

A man surrounded by the damage caused by the tsumani at Patong beach in Phuket - the island the Searles were on at the time

In 2004 parts of Indonesia were destroyed by the tsunami on Boxing Day

An image which captures the moment people fled from a tidal wave approaching the coast in Phuket

Once she found safety, Ms Searle waded through the water in desperate search for Lachie.

'I saw Elise and I asked where he was and she said she had to let go because they were getting pulled out by the water again,' Ms Searle said.

'When she told me that I just screamed.' 

But there wasn't much time for Ms Searle to grieve as she was alerted of a second tsunami that was on its way.

'I could hear whistles blowing and people were yelling that the next wave was coming soon,' she said.

She was rushed to higher ground where she met her husband and told him the devastating news.

'I told my husband at the time that I'd lost Lachie,' Ms Searle said.

'Brad just took off and I didn't see him for awhile because he went looking for our son.' 

Once the worst had surpassed, everyone was taken up to the roof of the hotel where Ms Searle had to play the painful waiting game.

'When I finally saw Brad up on the roof he told me that he couldn't find Lachie and I just lost it,' she said.

'I was hysterical. Sobbing and screaming. I started to feel bad and there was so much guilt.

'I had all sorts of things going through my mind - like bringing back Lachie's body bag and packing up his bedroom back at home. I wasn't sure how I would get through his birthdays and the Christmases without him.'

For Lachie, who's now 15, the fear and the memories of his nightmare holiday still remain

Mum Jillian is grateful each year to spend Christmas with her boys Lachie (left) and Blake (right) 

Blake, now 11, is also lucky to be alive after being pulled under water several times during the tsunami

An hour had passed and Lachie was still missing. Ms Searle was convinced she would never see her son again.

'I thought he was dead. Lachie couldn't swim,' she said. 

'So by that point everyone knew I'd lost Lachie but then someone said: "hey isn't that the Lachie who's been missing?".

'I opened my eyes and tried to wipe away my tears because everything was so blurry that I couldn't see. But then I saw a blue rashie - one that Lachie wore - and I just knew it was him.

'I just couldn't believe he was there, right in front of me.

'He didn't even have a scratch on him. He was perfect and was found by some security guards. And the first thing he said to me was "mummy I'm really dirty, I need a shower".

'I felt really lucky. It obviously wasn't our time and somebody was watching over us.

'Amazing - that's one word to describe it.'

A woman offers prayers on a tiled memorial wall in Thailand displaying names of victims from the Boxing Day tsunami that left more than 230,000 people dead in 14 countries

Family members of victims stand in silent memory after placing flowers into the sea in Thailand

Although Lachie, who's now 15, doesn't remember much of the day he remembers hanging onto a door for a couple of hours.

'I don't know how I survived but I guess when you're in survival mode and that strong mentality, you really don't know your own strengths,' he told Daily Mail Australia.

'I didn't even know what a tsunami was. I was only five. I just knew it was this big wave that wiped out everything.' 

In hindsight, Lachie says his mum made the right decision in letting him go.

'My brother was younger and had no chance of survival,' he said.

'I knew it had to be done and I think mum made a smart decision.'

While the Searles were the lucky few who lived to tell their tales of survival, there were more than 5,000 people killed in the tsunami that struck Thailand - 26 of which were Australian.

A decade on, commemorations have begun for the thousands of lives lost during the disaster.

The tsunami, triggered by a 9.1-magnitude earthquake, hit just off the west coast of Sumatra, Indonesia and struck coastal communities across the Indian Ocean. It left about 230,000 people dead.

But since the terrifying ordeal, Lachie and his family haven't been able to go back to Thailand.

'I think I'd like to go one day for a bit of closure but I just wouldn't put the boys through that at the moment,' Ms Searle said.

For Lachie, the fear and the memories of his nightmare holiday still remain. 

'Maybe I'll go when I'm a bit older but I wouldn't like to go now,' Lachie said.