Stephanie Davies, from Monmouth in Wales, bought the winning lotto ticket after hearing the news her mum had been given the all clear from cancer.
Sonia, 53, had just undergone keyhole surgery to remove a tumour in the parathyroid gland in her neck.
After hearing her operation was a success, she had a gut feeling a winning streak was on the cards – and she was right.
Her daughter rushed out and bought six Lucky Dips from the Overmonow Gargage in Monmouth.
One evening she headed upstairs and said to her 30-year-old boyfriend Steve: “If I shout down it means we’ve won the lottery and if not, I’ve gone to bed.”
And, very quickly the house was filled with joyful screams as the young sales executive realised they’d bagged the eye-watering £61million jackpot.
Her winning EuroMillions numbers were 01, 21, 26, 40 and 50, while the lucky star numbers were 02 and 04.
Stephanie said at a press conference at the time: “I came back downstairs to find Steve and couldn’t take my hand away from my mouth in shock.
“I kept saying ‘we’ve won and I’m not joking’.
“I could see Steve was trying to read me to see whether I was telling the truth but I was so emotional, he decided to check.
“And he checked again. We giggled. We memorised the numbers and checked again. We checked the draw date again.
“We locked all our windows and doors and spoke in hushed voices just in case someone could hear that we had won.
“It was all very MI6 – very secret service!”
When she called her mum to share the amazing news, all Sonia could hear was sobbing.
“I was worried there was a problem. All I could hear was Steph sobbing down the phone and the odd muffled word,” she explained.
“I thought she’d told me she’d lost her dog.
“Then I heard Steve shouting ‘we’ve won £61m’!”
She added: “Winning is just like living the dream.”
‘I JUST PUT MY HEAD IN MY HANDS’
However, there was someone who wasn’t too pleased to hear about the massive win.
After becoming a multi-millionaire, Stephanie decided to split the cash five ways with her family.
Mum Sonia and sister Courtney, 19, each enjoyed a £12,220,488.58 share of the enormous jackpot.
Stephanie’s partner Steve, 30, and Sonia’s partner Keith Reynolds, 55, were also handed the same fortune.
But, Daniel White, Courtney’s ex-boyfriend narrowly missed out on the same privilege.
The childhood sweethearts had split up just months before the cash windfall, after the pair parted ways when they went to university.
Daniel said: “It was a school and teenage romance which just tailed off.
“We had different interests and different friends.”
To add insult to injury, he was living next door to Courtney’s lucky sister.
He said at the time: “All my mates are savaging me – the first I knew of their win was my phone going nuts.
“The boys were all sending me links and jokey Snapchats asking if I was gutted. One said ‘how much have you cried since you found out mate?’
“I just put my head in my hands. I’m happy for them – but obviously I feel like it could have been me.”
Daniel later joked: “Courtney could give me a million a year for the two years I went out with her – I wouldn’t say no to that.”
And, he had to watch his ex’s new partner enjoy the winnings.
Stephanie had called her younger sister at 1.45am while the teenager was in Reading with her boyfriend Kieran.
Courtney said: “Steph just kept saying she didn’t know what to do.
“She then said we’d won the lottery.
“We kept repeating ‘oh my god’ to each other, over and over. In the end we had to say bye and hang up as we were so in shock we weren’t actually talking to each other.”
Kieran, a student at the time, was over the moon about his girlfriend’s win and had “high expectations” about his 21st birthday gift.
However it does appear Daniel, who used to work for the Welsh Rugby Union, has refound love and bought a house with his new partner.
Photos shared on Facebook show the grinning couple holding a set of keys outside the property.
‘ROLLER COASTER OF A WEEK’
The Davies’ family win came at an incredibly tense time for Sonia and her children.
After recovering from cancer and scooping her life-changing win, she said: “What a roller coaster of a week we’ve had.
“I had my operation on Wednesday and until then, we didn’t know how serious it was.
“They told me that if it hadn’t been removed it would have been fatal – and at the very least I would have lost my voice within a year.
“They managed to give me the all clear straight after the operation, so as you would imagine, we were on cloud nine.
“We were about to return home to celebrate our brilliant news.
“Keith was scanning his emails and read about the EuroMillions rollover.
“He was convinced that we were the luckiest people on the planet and definitely on a winning streak after the success of my op, so we called up my daughter Courtney to ask her to go and buy a ticket.
“She was travelling and wasn’t able to change her plans so we called Stephanie instead as something told us we needed to get a ticket – and the rest is history!”
Daughter Stephanie and her partner Steve bought their first house together that Christmas with the hopes of renovating it.
The 23-year-old also planned to splurge on a luxury Caribbean holiday.
Sonia and Keith, who works as a Regional Director, looked forward to sharing their win with family and friends.
A National Lottery spokesman said at the time: “What an amazing win for the UK – the fourth EuroMillions jackpot to be won here this year.
“We’re delighted the ticket-holder has come forward to claim their prize and their ranking of 10th place in the National Lottery rich list.”