Smiling sweetly for the camera in their smart school blazers these two sisters look the picture of childhood innocence and future promise.

Contrary to appearances, the two sisters were already involved in alcohol and drug use, skipping classes, and staying out late into the night. Subsequently, their behavior escalated to randomly attacking strangers for entertainment.

Within three years of the photograph being taken, the sisters’ swiftly deteriorating behavior culminated in them murdering a stranger—a senseless act of street violence that shocked even the most experienced police officers.

When one sister was detained on suspicion of murder, she casually told the police: ‘My New Year’s resolution was not to get arrested this year. It’s already ruined and it’s not even March.’

She was 16 years old.

Recently, a Daily Mail investigation has revealed unsettling details about the sisters’ upbringing, particularly the negative impact of their extremely violent, drug-addicted father, which contributed to their appearance at the Old Bailey courthouse.

Last Friday, at that London courthouse, the sisters, along with another schoolgirl friend, stood in the dock and pleaded guilty to the unprovoked murder of Fredi Rivero, a frail elderly man suffering from cancer.

Aged 14 and 16, the sisters, together with a 17-year-old friend, hounded Mr Rivero as he waited for a bus home this February.

The girls pushed and kicked at the 75-year-old retired hotel worker, taking his glasses to render him more defenceless, ignoring his repeatedly desperate requests for them to leave him alone.

In a horrible note of irony, Mr Rivero, a practising Buddhist, at one point even made a peace sign – the very same gesture the sisters make in the photo above – in an attempt to calm them down before he was punched unconscious to the floor.

It did nothing to stop the violence.

Mr Rivero was rushed to hospital following the sickening attack on the Seven Sisters Road in North London but died the following day from a head injury.

The incomprehension at how girls this young could become so out of control, was perhaps best summed up by their victim’s daughter.

‘They assaulted my dad at 11.30pm,’ she said. ‘My question is – how can girls their age be out at that time?’

Last Friday were jailed for a total of nine years, with the 17-year-old given four years detention, the 16-year-old – who has now turned 17- three-and-a-half years’ and her younger sister two-and-a-half years.

The sentence could – and most will perhaps think should – have been considerably longer.

But Her Honour Judge Judy Khan KC said she was taking into account their guilty plea and noted all three – who cannot be identified because of their age – had ‘unusually traumatic upbringings’.

The Crown had accepted a guilty plea to a manslaughter charge rather than prosecute them for the much more serious offence of murder – and an order was imposed on the media prohibiting the girls being identified.

The only photograph in the Met Police announcement of their conviction was of a generic ‘scales of justice’.

But today the Daily Mail is able – insofar as those legal constraints allow us – to publish pictures of the sisters for the first time.

And we have pieced together details of their escalating criminal careers in the months leading up to that killing.

So how did their lives go so wrong so quickly – and what was the nature of this ‘unusually traumatic upbringing?

The pair grew up a short distance from the notorious women’s prison at Holloway – where they may even be transferred once they reach adulthood and become too old for youth custody.

In their infancy they lived with both parents and brother in maisonette in North London – a home life that was initially relatively stable compared to what was to come.

This stability was underpinned by the full time job that their father held as an ancillary worker at an airport.

Commuting daily from north London to the airport must have been gruelling and their father wasn’t able to sustain his commitment for long – and he began taking drugs.

Inevitably he soon lost that job as he became hopelessly to crack cocaine and his downward spiral was rapid from this point.

He was soon lying, stealing from friends, begging from neighbours to feed his addiction – which began to take over his and the family’s life.

When he resorted to stealing his children’s Christmas presents from under the tree to sell to raise cash to feed his habit, one would think he had reached a nadir.

He hadn’t.

In 2018 he decided to rob a friend and near neighbour he had known for more than 20-years.

He knocked on the friend’s door ostensibly for an impromptu social visit but as soon as that friend’s back was turned he hit him over the head with a truncheon before grabbing a knife from the kitchen drawer and stabbing him repeatedly in the back.

As his victim lay sprawled on the floor, he stabbed him in the throat and grabbed what he had come for – his victim’s life-savings, amounting to more than 10,000 in cash.

His friend, who had been stabbed eight times, feigned death to stop the attack and it was only for this reason that he survived – but he was left paralysed.

The girl’s father was sentenced to 20 years for wounding with intent to be served concurrently with a nine year and six months sentence for robbery, four months for possession of an imitation firearm and seven days for possession of class A drugs.

Criminologists often grapple whether it is ‘nature or nurture’ which sees people become offenders – but these sisters were disadvantaged on both fronts, the daughters of a violent monster and a mother who struggled to cope.

The absence of any father-figure from the time when they were respectively in Year 3 and Year 5 of primary school – together with the lack of a competent mother – played a pivotal role in the girls turning to crime and anti-social behaviour, it seems.

They quickly went from exuberant and cheerful girls into vodka-swilling and cannabis-smoking yobs who enjoyed violence as a passtime.

One former friend remembered: ‘I grew up nearby and used to see them playing in a park behind the flats.

‘In those days they were nice kids and the family seemed decent enough.

The school they went to is rated ‘outstanding’ by Ofsted – but its influence was not to arrest their gravitation towards serious crime.

Their childhood friend continued; ‘They changed as they got older and as their house became ravaged with alcohol and hard-drugs.

‘Their dad would go round to people who lived nearby and ask to borrow money – saying he needed help in feeding his family.

‘It was a lie of course, he needed it for drugs and he never paid anyone back.

‘When he went to prison for nearly stabbing his friend to death, I noticed an even bigger change in the girls – they became much more aggressive.

‘Despite being only young teenagers they were drinking alcohol and openly smoking weed outside their house.

‘Their mum didn’t seem to care one bit as the flat by then had become something of a drugs den.

‘The family would have loud parties that used to go until the early hours of the morning, even during the week when they should have been getting up for school.

‘And the two girls became hostile and threatening to people they saw in the street when previously they’d got on well with everyone.’

It was against this backdrop of drug and alcohol abuse interspersed with routine violence that the two sisters would soon run amok in the streets, beating up rough-sleepers, trashing local shops and restaurants and taunting passers-by, recording much of their ‘hijinks’ on a mobile phone.

And joining them on many of their escapades was the 17-year-old friend of the older sister.

She too came from a dysfunctional background and had been placed in care in Kent – but returned regularly to the area to see her father in London and to hang out with the two sisters.

And matters came to a head in a chance encounter which was to prove fatal on February 27 this year.

At 11.17pm that night, the two sisters and their friend were getting off a bus on the Seven Sisters Road where Bolivia-born Mr Rivero stood waiting.

The younger sister was clutching an open, half-drunk bottle of vodka as her older sibling deliberately bared into their chosen victim’s right shoulder.

What followed was a sickening assault caught on CCTV that left the country horrified that three teenage girls could inflict such ferocity on an older man.

The footage – played in court – showed Mr Rivero backing away and flashing the peace sign to try to break the tension.

However the 17-year-old girl is seen shoving him towards a nearby shop front and pulling his glasses off his face while the older of the two sisters started filming on her phone.

Mr Rivero retrieved his glasses from the floor but was pushed backwards and kicked by both sisters who follow him until their friend, who turns 18 next month, punched him to the floor.

The girls hovered around him as he lay unconscious in a pool of blood on the floor pleading self-defence to those who had run to his aid, falsely accusing their victim of touching one of them inappropriately.

They fled the scene but were later picked up by police. The 17-year-old girl was arrested at her father’s flat.

The two sisters, meanwhile, were picked up at a children’s playground near the Seven Sisters Road and were both quick to blame their older friend for the death – and to further blaime the victim himself.

In interview, the elder of the two, who has previous convictions for assault, told detectives: ‘I’ll be so real, that’s his fault, he started on us, (the eldest girl) pushed him, and he lost his balance and he fell.’

It was while making these feeble excuses that she let slip that she had broken that New Year’s resolution by being arrested – just nine weeks into the new year.

Her younger sister told police as she was arrested: ‘It wasn’t me. I promise I know who it was, it was my sister’s friend.’

Prosecutor Louise Oakley said former Mayfair hotel worker Mr Rivero was an innocent victim who did nothing to provoke the attack and ‘simply wanted to get home’.

She added: ‘The violence and humiliation they inflicted on him was gratuitous.’

Videos later seized from the girls’ mobile phones showed a string of violent incidents against other members of the public previously.

The Daily Mail can reveal that these included one clip showing the younger sister holding a bottle of vodka while assaulting a young homeless woman outside a shop.

Another showed an incident where both sisters and their older friend were drunk and were filmed hitting a man outside a restaurant where tables had been overturned.

There were also videos of the older sister grabbing a woman in the street and hurling her to the ground and chasing after another woman calling her a ‘fat f****** b***h’

The 17-year-old girl was also found to have recorded a video where she confronted a man calling him a ‘paedophile’ and threatening to hit him.

Their attack on Mr Rivero was captured in a 1.52 minute mobile phone clip in which he was heard begging the girls ‘I want to go home, I want to go home’

They responded by laughing and mocking him.

The older of the two sisters drunkenly slurred ‘Don’t f****** touch me, bitch’.

Detective Inspector Devan Taylor, who led the Metropolitan Police investigation, said: ‘This was a completely unprovoked attack by three teenage girls, on an elderly man who was just going about his day.

‘The fact they filmed the attack and found it funny is even more sickening.’

Mr Rivero’s family have been left heartbroken by his death.

In her victim impact speech -which was given from behind a screen so that she did not have to look at or be seen by her father’s killers – Mr Rivero’s daughter tried to convey her incredulity that such young girls were out so late at night in the first place.

She continued: ‘I will never forgive these three offenders for cruelly and maliciously killing my dad.

‘He was an ill, elderly person who would never hurt anyone. His death makes the crime irreversible.’

‘We should be living in a society where we can have a conversation and even disagree without resorting to violence.’

There is one more person to hear from in this sorry tale – and that is the victim of the girls’ father’s equally horrifying violence.

Now confined to a wheelchair, the victim of that attack and robbery says his former friend destroyed four lives the day he stabbed him.

He told The Mail: ‘I’ve heard about what happened with his daughters and I’m not surprised at all.

‘They were lovely girls once – but what chance did they have with a worthless piece of s*** for a dad?

‘I’ll tell you – absolutely none. Not with that crack-addict scumbag.

‘What kind of man robs his own children’s Christmas presents to sell for drugs?

‘Their mum didn’t give them much of an upbringing either – she was all over the place herself and not a fit parent.

‘I’d known their dad for over 20-years when he left me for dead. He was after my savings – because he owed a lot of money to Albanian drug dealers.

‘But what did he achieve?

‘He left me paralysed down one side and in need of a wheelchair, he got himself banged up on a 20-year-stretch and he set his daughters on the same path as him.

‘They killed a defenceless old man and are now locked up like him. If you ask me they didn’t get nearly a long enough sentence – but with an upbringing like that it’s no surprise they’ve ended behind bars.’

The sort of attack which killed Mr Rivero – in which gratuitous violence is meted out by being filmed – were once widely known as ‘happy slappings’.

This was a misnomer as they brought nothing but misery for all involved.

Rarely has this been truer than in this disturbing case.