The Making of the Schoolgirl Killers 😱 From Model Students to Savage Gang Members #TrueCrime #News

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

But nothing could be further from the truth: the pair were already dabbling in drink and drugs, skipping school, staying out until the early hours - and would soon be attacking random strangers for kicks.

Because, within three years of this picture having been taken, the rapidly escalating criminality of the two sisters would see them kill a stranger in a gratuitous street attack that has horrified even veteran police officers.

When one sister was first picked up on suspicion of murder, her police response was: 'My New Year's resolution was not to get arrested this year. It's already done and it's not even f****** March.'

She was 16 years old.

Now, a Daily Mail investigation has uncovered disturbing, or perhaps even horrifying details of the two girls' childhoods - and how the malign influence of a terrifyingly violent drug addict father set them on the path to the Old Bailey.

It was at that London court last Friday that the pair - along with another schoolgirl friend - appeared in the dock to plead guilty to having killed frail, cancer-suffering pensioner Fredi Rivero for no reason.

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 defenseless, ignoring his repeatedly desperate requests for them to leave him alone.

In a horrible note of irony, Mr Rivero, a practicing 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 the 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 11.30 pm,' 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, 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 Honor 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 offense of murder, and an order was imposed on the media prohibiting the girls from being identified.