The father of two little girls has told a court of his emotional anguish after their mother was convicted of killing the girls because they were interfering with her x-rated social life.

British woman Louise Porton, was convicted on Friday of the murder of her three-year-old daughter Lexi Draper, and 16-month-old Scarlett Vaughan. The two died 18 days apart in early 2018.

While doctors were initially unable to identify a cause of death, both were said to be consistent with “airway obstruction”.

View photos Ms Porton posed for fetish photo shoots with strangers on the internet (left). The daughters during a recent Christmas (right). Source: PA More

The 23-year-old denied killing the girls but the prosecution “successfully proved that Ms Porton squeezed the life out of them” because they were getting in the way of her sex life.

Mr Porton, a self-described model, would meet men online and charge them for fetish-related photo shoots and sexual acts.

She continued to contact and engage multiple men on dating sites in the days following the deaths of her daughters, accepting 41 friend requests on a dating app a day after the first death.

On the night Lexi died, Ms Porton searched for information about the period that resuscitation was still effective as well as information on the time it takes for a body to go cold.

During sentencing, judge Mrs Justice Yip described Ms Porton’s internet browsing as “sinister” and labelled the crimes as “calculated” and “evil”.

"One way or another you squeezed the life out of each of your daughters, only calling the emergency services when you knew they were dead,” she said.

"These were blameless young children who were plainly vulnerable and ought to have been able to rely on their mother to protect and nurture them.

"Instead you took their young lives away."

Ms Porton will serve a minimum 32 years in prison.

View photos The final moments of the girls were caught on CCTV. Source: Crown Prosecution Service More

Father tells court of heartbreak in scathing statement

The Birmingham Crown Court heard an emotional victim impact statement from the children's father, Chris Draper, who said he was a "broken" man and was left wondering how Ms Porton could do something so horrible.

"Why did Louise do something so evil to our beautiful daughters? You are their mother, the person supposed to care for them, protect and love them,” he said.

"They were just an inconvenience to you; how could you do this?

"I sit and think day and night and I can't understand why my two little girls were taken away because Louise wanted to sleep around."

Mr Draper said he’ll never get to do the normal things a father looks forward to.

“Because of Louise I will never hear them, I will never hold their hands or take them to school like a normal dad,” Mr Draper told the court.

View photos Police said the mother was calm and emotionless after the deaths. Source: Warkwickshire Police More

Mum was planning a holiday before killing the girls

According to one anonymous friend, Ms Porton was intending to go on a holiday to the Greek island of Magaluf - a renowned party destination for British holiday-makers.

“She had been talking about it for ages. This was before she killed her kids,” the female friend reportedly told The Sun.

“She said she’d been [to Magaluf] when she wasn’t a mother and slept with loads of blokes,” the friend said.

“She was looking to go in the summer of 2018 but by that time the police were already on to her.”

Do you have a story tip? Email: newsroomau@yahoonews.com.

You can also follow us on Facebook, download the Yahoo News app from iTunes or Google Play and stay up to date with the latest news with Yahoo’s daily newsletter. Sign up here.