A mother who murdered her two young daughters 18 days apart after they “got in the way” of her living the life she wanted has been jailed for at least 32 years.

Louise Porton, 23, killed Lexi Draper, three, and 17-month old Scarlett Vaughan last year. Both deaths were consistent with deliberate airway obstruction, and doctors could not find “any natural reason why either, let alone both, should have died”, prosecutors said.

She suffocated Lexi in the early hours of 15 January, and was heard “laughing” at a funeral parlour two days before killing Scarlett on 1 February.

A jury heard that Porton, who described herself on a dating app as a model, accepted 41 friend requests from men the day after Lexi’s death.

After Scarlett’s death, she had delayed calling an ambulance, even filling up with petrol as the toddler lay dead or dying in her car, and was described as being “calm and emotionless.”.

Her children “got in the way of her doing what she wanted, when she wanted and with whom she wanted,” Oliver Saxby QC, prosecuting, said.

Porton, of Skiddaw, Rugby, Warwickshire, denied killing the girls, but was unanimously convicted following a five-week trial.

Jailing her for life with a minimum term of 32 years the judge, Mrs Justice Yip, described Porton’s actions as “evil” and “calculated”.

“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. I am sure at the time of the deaths, you intended to kill each of your daughters. Why you did so, only you will know.”

Evidence pointed to Porton having made two previous unsuccessful attempts on Lexi’s life. She had twice been taken to hospital but was sent home with antibiotics for an apparent chest infection.

The judge said she was sure Porton had been responsible for events leading to Lexi’s earlier admissions to hospital on 2 January and on 4 January when her life was saved by skilled resuscitation by paramedics.

Porton had made “sinister” internet searches at the time about death and breathing and drowning. She had researched how long it took for body parts to go cold, Birmingham crown court heard.

The crown alleged Lexi had been dead for some time before a 999 call was made. Of Lexi’s death, the judge said: “I am left in no doubt that you delayed calling for an ambulance until you were sure she was dead and could not be resuscitated.” Scarlett “had signs of prior airway obstruction”, the judge said.

When Lexi was ill in hospital, Porton took topless photos in the hospital toilets and was arranging to perform sex acts for money with a man she had met through a website, the jury heard.

After Lexi’s death, it appeared to the funeral arranger present that Porton was “using FaceTime and that she was speaking to a man.”.

Porton’s former landlady, when she lived at an address in Willenhall, near Walsall, told police she spent “more and more time” caring for Lexi and Scarlett while their mother was “doing social things” instead of looking after them. Porton would do “whatever she could not to have them with her”, she said.

Facebook Twitter Pinterest Lexi Draper (left) and Scarlett Vaughan died in early 2018. Photograph: Warwickshire Police/PA

Porton had denied wrongdoing throughout, telling police in a prepared statement: “My children were never an inconvenience to me and I accommodated my lifestyle and personal life around them. I still don’t know how my daughters died, or what caused it.”

The judge said she had carried out the “grossest abuse of trust” against her girls. “Those who loved Lexi and Scarlett have been left bewildered as to how and why you could have done something so evil.”

The children’s father, Chris Draper, who never met Scarlett, said in an impact statement he felt “broken” with “nothing to live for”.

“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. Maybe if social services had listened to me, my girls would still be alive today.”

Det Supt Pete Hill, of Warwickshire police, said: “I will never be able to understand why Louise Porton murdered her children; Lexi and Scarlett. Not content with killing one of her children, she did exactly the same to her other daughter.”