The body of Paul Pearson, 28, a doorman from Preston, was discovered on Sunday morning (July 14) after police were called to the home he shared with his father in Avenham.
At 6.39am, officers knocked at the Greenwood Street home after receiving concerns about his welfare.
His father, Paul Pearson Snr, had been on holiday in Tunisia and had become increasingly worried after his son failed to answer his calls.
Paul Sr said he had last spoken with his son on Skype in the early hours of Thursday morning (July 11).
Receiving no response at the home, officers entered the property and discovered Paul's body in his bed.
The father-of-three was pronounced dead at the scene. A file has been prepared for HM Coroner.
Police said they had recorded the incident as a 'sudden death', but confirmed that there are no suspicious circumstances.
A post-mortem examination has since revealed that Paul died from sleep apnoea - a disorder that affects people's breathing whilst they sleep.
According to the NHS, sleep apnoea is a very common condition, where the walls of the throat relax and narrow during sleep, temporarily cutting off the airways.
It is believed that as many as 1.5million people suffer from the condition in the UK. But the disorder is rarely fatal.
His grieving father told the Post how the family have been left 'shell-shocked' after losing Paul to the sleep disorder.
"Paul had recently become a proud dad for the third time after his youngest, Anastasia, was born 15 weeks premature in May.
"To lose him at such a young age - he was only 28 - is such a shock.
"But for to lose him because of his sleep apnoea - we're all just shell-shocked.
"It's not something we really worried about that much, neither did Paul.
"He was a big lad and had put a bit of weight on in recent years, and his sleep apnoea was part of that.
"But it wasn't something we worried too much about. It was just something he lived with."
Paul's dad said his son began to suffer from sleep apnoea after he began to put on weight in his early 20s.
But he said Paul had recently been determined to get healthy after becoming a father for a third time in May.
In recent weeks, father and son had even taken up kickboxing together, as Paul strove to become fighting fit for his children.
In a moving tribute to his son, his father told the Post how Paul was "more than just a son. He was also like a brother and best friend".
"He was everything to me", said Paul Snr.
"I was the first person to hold him when he was born and we lived together for most of his life.
"We were very close me and Paul. We were like best friends and brothers, as well as father and son.
"We'd spend most nights together, watching films, poking fun at each other, and talking about motor bikes, which we both loved.
"My life's not going to be the same without him. It just doesn't seem real. I can't imagine life without him."
Paul Snr said he is most proud of his son for the way he provided for his three children - three-year-old Poppy-May, ten-month-old Roman and two-month-old Anastasia.
"Those three kids were his world", said Paul Snr.
"Everything he did was for them. All he tried to do was work hard, so he could provide for them.
"Whether it was packing parcels at Amazon or working the doors in Preston, he just did what he could to provide for his kids.
"That's why I'm hoping to raise a bit of money through JustGiving,to help give them a bit of security for their future.
"Paul would have always worked hard, scrimped and saved to make sure they wouldn't go short, but now he's not around to look out for them.
"The kids are what Paul cared most about, and I want to make sure that we do him proud, just like he made me proud.
"If we can raise a bit of money for them, to make sure they're taken care of, that's all he would have wanted.
"Any kind donations, big or small, every little penny will be very much appreciated."
To donate to Paul Pearson's JustGiving campaign, click here.
To learn more about sleep apnoea, read our explainer here.