The tweets documenting one Irish man's random act of kindness has gone viral, sparking an outpouring of support for a cancer victim.

Cara Grace Duggan, wanted to buy a Nutribullet, which is a smoothie maker, for her mother Kim, who was diagnosed with stage 4 oesophageal cancer last year, the Daily Mail reports.

Duggan wanted to encourage her mother to try alternative therapies after doctors told them they would not be able to cure the aggressive disease, just 'prolong her decline.’

Kim adopted a vegan alkaline diet and Duggan wanted to buy a Nutribullet for her mother. However, she couldn't afford the model needed for her dietary requirements.

Speaking to FEMAIL about her mother's condition, she said: “My mum has been suffering with nausea due to the cancer and a blood clot, so we thought it would be a great way to get nutrition into her. We needed the 900w so we could also add her supplements and they would be grinded into the juices.” 

The mother-of-two spotted a secondhand version on Gumtree and contacted the seller.

“Hi there, I was wondering if you still have your nutriibullet for sale and if so would you consider posting it?” she wrote.

“I could pay via PayPal so we're both protected? I've been looking for one for my mum as part of her cancer treatment but just can't afford the £130 price tag.”

The man replied saying: “I’m sorry to hear that your mum have cancer, just send me your address i will post it you and you don't have to pay for it. I also pray for your mum. 

“And if there is anything i can do for you plz let me know [sic].”

The pair exchanged a few text messages and Cara Grace received confirmation that the Nutribullet was en route with a text from the man saying: “Its paid now plz collect it today as i don't want you and your mum to wait for nutribullet. 

“If you have any problem in collecting order or need any info to collect the order plz don't hesitate to contact me.’”

Realizing that the man had bought a brand new Nutribullet for her mother, Duggan text him saying: “Oh my goodness! Why are you so kind! 

“Thank you so so so much! I don't even know what to say! My baby is sleeping but when he wakes I will go and collect! Thank you so much!”

To which the man replied: “Don't say thanks to me. In fact thanks to you for giving me this opportunity.”

Said Duggan: “I didn't really understand it! I thought he meant we could do "click and collect" in Argos. So when the lady actually handed me the nutribullet I welled up. I just can't believe a stranger would do this for someone he doesn't know.

“My mother had been feeling really terrible for a few days there but now she's got her smile back - it's incredible!”  Since her story went viral, people from around the world have been making donations to support her mother’s battle with cancer. 

She expressed her gratitude towards the stranger, saying, “Thank you so much, you had no idea just how much of an impact you would haven our lives. Since the story went viral, people have picked up on mum's story and our fundrasing efforts, and we've had £5,000 donated in one day. It's all thanks to you and we honestly can't thank you enough.”

Despite his kind act, the man wishes to remain anonymous.

“I’ve spoken to him today and he says he wants to remain anonymous. He said he didn't do it to show off, he just hopes one day I can text him and say mum is cancer-free,” said Duggan.

The man’s contact information is now saved in Duggan’s phone as “the kindest man ever.”

Duggan and her family have set up a GoFundMe page, which you can visit here