Wealthy widow Maureen Cosgrove did not like her prospective son-in-law one bit.
To her eyes, George Maben was using her 34 year-old daughter Lucy Rees to get a free ride. He was jobless, lazy and inconsiderate. He tossed his cigarette butts in her flower beds at her £700,000 home in Carshalton Beeches, Surrey. He kept leaving his jacket over a chair instead of hanging it up. No matter how many times she told him, he never took any notice.
'They would argue over silly irrational things,' said Miss Rees. 'He wouldn't take his shoes off when he walked into the house.
'He had been staying there rent free. He was not working, and I was seven months pregnant.'
After a series of arguments, Maben went back to live with his mother in her two-bedroomed home in Morden, Surrey, and was only allowed to stay over with Lucy at weekends.
On March 24, 2009, Maben arranged to meet his partner outside his local Co-op but never turned up. Instead he rang and asked to meet her in nearby Sutton to go shopping and have a drink.
During the trip, Lucy made a series of calls to her mother but failed to get an answer.
When they returned to Mrs Cosgrove's home, they discovered her body lying on the floor. She had been strangled with a ligature.
Maben - known as Geordie - patted her on the cheek and said: 'Maureen wake up.'
Paramedics arrived within minutes and suggested there may have been a struggle because the back door was open.
'I just assumed it was a burglar,' said Lucy Rees. 'Geordie told me I needed to sit down. He was shaking.'
During the investigation, detectives treated both Maben and his partner as suspects.
Mrs Cosgrove, a retired teaching assistant, was worth over £1 million and owned a house in Gerona, Spain, following the tragic death of her husband Terry two years earlier.
Her missing handbag - at first believed to have been taken by a burglar - had been tossed into a neighbour's garden.
Police also found footage of Maben taking a bus to Mrs Cosgrove's home earlier that day and he had been caught on CCTV wearing a hat, coat and pair of gloves.
Another camera showed him dumping the jacket on the route from Carshalton to Sutton. Once recovered, fibres from Mrs Cosgrove's clothes were found upon it. The gloves were later found in a bin.
Knowing the case was weak, detectives decided to bug the couple's Ford Focus before returning it to them when they were released on bail.
Officers then called the pair while they were both in the car, hoping to spark a conversation about the murder.
And when Lucy got out of the car to go to the shops, Maben was heard making an extraordinary confession.
He prayed: 'Please God help me, please God help me, for me and Lucy eliminated from all police inquiries and everything all right.
'Please God help me, God forgive me or what I have done. I just couldn't take it any more. Every single day she was breaking me down. Please God will you forgive me.'
Here was the breakthrough the police needed to charge Maben with murder. The confession also provided the shocking motive for the killing - Maben had been worn down by Mrs Cosgrove's nagging.
Prosecutor Anthony Glass QC later told the Old Bailey: 'Clearly relations between the defendant and his grandmother had seriously deteriorated.
'With her out of the way the defendant could see a future for himself, Lucy, her children and the unborn baby unencumbered by any constraints imposed by Maureen Cosgrove.'
During the Old Bailey trial in October 2009, Maben admitted going to the house on the day of the murder but claimed he was spying on his girlfriend because he thought she was cheating on him.
He said the confession actually related to the theft of £50 from his own mother's purse.
Mrs Rees, who had two children with a previous partner, told jurors she had questioned Maben about the murder before his arrest.
'I remember on a couple of occasions asking "Did you kill mum?" and he said no and I said "I didn't so we have nothing to worry about".'
Mrs Rees denied suggestions that she had been involved in the murder and said she could not believe her partner was the killer.
'I still love him today. I wish, I hope he hasn't done it but if he has he's got to pay for it,' she said.
Maben, who is originally from Dunganen in North Ireland, was convicted of murder by the jury and jailed for life.
In a controversial move, Judge Jeremy Roberts QC ordered he should serve a minimum of 13 years behind bars after describing him as 'kind and caring.'
The judge said: 'I am quite certain that this offence was the result of a very unusual combination of circumstances and that it is wholly unlikely that you will do anything like this again.
'It is clear you are generally a kind and caring person and you have done a great deal of good, especially to people in serious problems who you have helped.
'It wasn't anybody's fault that the situation developed in which your relationship with Lucy, who you loved deeply, and her mother who you must have seen as an obstacle to you ever being able to enjoy the kind of life you wanted with the woman you loved and the mother of your child, drove you to such an act of desperation as this.
'The extent of your desperation is graphically demonstrated by your prayer for forgiveness which was covertly recorded by the police.
'Part of your punishment will be the irrevocable destruction of the relationship with the woman you love and the mother of your child.'
The minimum term was later increased to 18 years after the Lord Chief Justice ruled the original sentence was 'disproportionately reduced.'