Boyzone star Stephen Gately’s family are planning to hire a private investigator to re-examine his death, it has emerged.

The Irish pop star died five years ago at the age of 33 from an undetected heart condition while he was on holiday in Majorca with his husband Andrew Cowles.

But 36-year-old Cowles, who is expected to inherit 60 per cent of the singer’s estate, is now embroiled in a row with the Gately family.

Gately’s brother Tony has revealed that he would like the Spanish police to reopen the case, and intends to hire a private investigator to give his family answers about the death.

He said: “Only two people really know what went on the night he died. They are his husband Andrew and a Bulgarian guy, Georgi, who was invited to their apartment. Neither of them have fully explained to me what happened. We are looking at getting a private investigator once his estate is settled.”

The star, who was the joint lead singer of Boyzone, married his internet entrepreneur boyfriend in Las Vegas in 2003 — only a few months after the pair were introduced by Elton John.

The Dublin-born singer amassed a £3.3 million (Dh19.4 million) fortune and left £1.5 million after debts and taxes. However he did not write a will, so Cowles is likely to get most of his estate. The pop star’s parents are expected to take the rest.

His 32-year-old brother, a bus driver from Midlothian, claims the family no longer speak to Cowles — who allegedly tried to price the star’s possessions and then attempt to sell them to his family.

Gately told the Sun on Sunday: “Andy has put a price on every item we’ve asked for. Those things are tarnished now. Some of them were things that we had given to Stephen as presents. They were sentimental items. Stephen had a load of snow globes and we wanted some of them for the kids.”

He added: “He’s had all Stephen’s earnings and personal possessions. Our family have had none of that. At the minute it looks like Andy is going to get 60 per cent of Stephen’s estate. Our mum and dad will get a fraction, but the estate still hasn’t been settled.

“Our mum is 65 and was hit so hard by Stephen’s death that she has withdrawn into herself. It’s making her health deteriorate.”

Gately was found dead at his £1 million apartment in the upmarket Majorcan resort of Port Andratx. His body was discovered on a sofa by 25-year-old Bulgarian model Georgi Dochev, who stayed the night at the couple’s flat after an evening out.

A post-mortem examination revealed that Gately had been suffering from atheromatosis, or a thickening of the arteries, and died due to a pulmonary oedema — an accumulation of fluid on the lungs.

Although he had been drinking and had smoked cannabis that night, drugs and alcohol were not a factor in his death and the police stated that there were no suspicious circumstances. But his brother said: “Even now we are still not certain what happened and Andy has never opened up to me. A few things about that night don’t make sense.

“First of all, Stephen was on the couch and that does not seem like him. He once flew from London to Manchester, then to Dublin so he could sleep in his own bed.

“He loved his comfort, he would never fall asleep on the couch.”

He went on to say that it was strange that the couple had another man staying the night with them. He explained that Gately’s former boyfriend Eloy De Jong was “shocked that Stephen had done something like that”, adding: “I said to him, ‘Did anything like that happen with you and Stephen? Did you bring anyone else into the relationship?’ He said no.”

Gately added: “It still plays on my mind. We’ve tried to get to the bottom of it but to no avail. I still ask the questions and go over things. I would love the police to look into it again.”

Reflecting on the moment when he was told his brother was dead, he said: “I just fell to the floor. I remember screaming. My kids were there crying too. It was horrendous. Stephen was everything to me. He was my older brother. I looked up to him so much. We were so close.”

Cowles could not be reached for comment.