Mary shot to fame in 2007 with the inception of the TV show Mary Queen of Shops which saw her help failing high street shops.
She was then appointed by then Prime Minister David Cameron to lead an independent review into the future of the high street in 2011.
Mary’s brother Lawrence Newton provided the sperm to conceive Horatio with Melanie’s egg through IVF.
‘To be honest, I don’t know which child is more high maintenance!’ Mary told the Daily Mail in 2015, adding that she actually finds looking after her older children more challenging than her youngest.
‘The [then] 19-year-old has come back from her gap year and is going off to university this Autumn. I spend so much time giving emotional and loving guidance, it’s much more emotionally draining than the three year old!’
Mary also went on to explain her close relationship with her brother Lawrence, who she revealed earlier in 2015 had fathered her child with Melanie.
‘When you suffer a parent’s death you stick together like glue. So we were always close,’ she explained.
‘We are family, that is it… I am a mother, I am a businesswoman, I have children, I have family, I just happen to live with another woman and she had a child who happens to be from my brother. The more I am able to normalise that, the better the world is going to be.’
‘It’s much heavier emotionally to deal with daughters. I was quite glad I had another son,’ she confessed.
‘No offence to my daughter – who I adore – but they are full-on. It’s all those emotions that young girls go through.
‘From being accepted by their friends to how they look – there is a huge pressure on them that is not on boys.’
But the unconventional circumstances of Horatio’s conception have their roots long before all this. They lie in the tragic childhood during which Portas was effectively orphaned at the age of 16 — and became a surrogate mother to Lawrence, now the surrogate father of her child.
When she and her brother first carried the baby into the West London sunshine outside St Mary’s Hospital, Paddington, they could have been forgiven for reflecting on this extraordinary circle of life. Or as Portas puts it: ‘I now know that it could only ever have been Lawrence who was Horatio’s father.’
To fully understand those words, it is necessary to turn back the clock 40 years, to the days when the multi-millionairess retail and brand consultant was a feisty 16-year-old, harbouring dreams of becoming a famous actress and hoping to take up a place at RADA.
All that changed, suddenly and irrevocably, with the death of her mother, also called Mary, from meningitis in 1977.
While Portas’s three older siblings were already on the verge of leaving the family’s run-down semi-detached home in Rickmansworth, Hertfordshire, her grief-stricken father found solace with another woman — leaving Portas to care for 14-year-old Lawrence, to wash his clothes and feed him, while struggling to come to terms with her own broken heart.
She may have earned celebrity status through her TV series Mary, Queen Of Shops, not to mention her role advising David Cameron on the future of the High Street, but Portas’s beginnings were much more humble than her wealthy life today might suggest.
Her parents were immigrants from Northern Ireland; her red-headed, green-eyed mother, Mary Flynn, was a laundress and her father, Sam Newton, was a bus conductor. Both were hugely aspirational and encouraged their five children to study hard at their Catholic schools.
While Sam later became a factory manager for Brooke Bond, his wife devoted herself to raising her children, Michael, Patricia, Joe, Mary and Lawrence.
The sudden loss of their mother — erroneously diagnosed with depression caused by the menopause even as she lay dying — was made worse by the reaction of their father who, having flung himself sobbing across their mother’s body, declared that there was nothing left to live for.
However, he swiftly replaced his wife with another one after meeting office clerk Rebecca at a widow and widowers’ social club.
He then sold the family home despite the fact that young Mary, who had barely left school, and Lawrence, still studying, were still living there. Both were made homeless, and Mary developed a fierce independence and self-sufficiency still so evident today.
Everything in the house was sold or simply vanished. She has no photographs to remember her mother by, only a cookery book and a statue of a saint.
Despite Lawrence’s love of music, he was virtually ordered by his father to join the police force, largely because he would be given accommodation at training college in Hendon.
Yet despite her own ordeal, an ever‑capable Portas was never far from her younger brother’s side. She dropped out of her course at RADA because she couldn’t cope, financially or emotionally, and devoted herself to looking after them both.
Effectively, then, she sacrificed her dreams of becoming an actress to become Lawrence’s surrogate mother, unaware that one day he would step in and thank her in the most poignant manner imaginable, by becoming a surrogate father to her child after deciding that he didn’t want any of his own.
‘We are just so close,’ she told The Times at the weekend. ‘Our bond is never going to change, never ever going to change.’
Meanwhile, Portas grew up enjoying unequivocally heterosexual relationships and romantic feelings for men she met, eventually marrying chemical engineer Graham Portas after meeting him in a wine bar.
By then she had found considerable career success. After attending Watford College Of Art, Portas began her retail career in the early Eighties with a Saturday job in John Lewis before moving on to Harrods, where she got her first experience in designing window displays.
She moved on to Topshop before being poached by London department store Harvey Nichols, where her extraordinarily creative window displays made her the talk of London. She was a board member by the age of 30.
For a while it seemed her professional success was matched by domestic happiness. Her son Mylo, now 21, was born in 1994. Her daughter Verity, now 19, nearly two years later.
But slowly, the relationship began to fall apart and the couple divorced, very amicably, in 2003 after 13 years of marriage. She has since described those as ‘some of the best years of my life…we just grew apart, and that happens.’
It was not long afterwards that Portas met Melanie Rickey, a magazine fashion features editor, at a Royal College Of Art dinner, and the pair fell for each other almost immediately.
Until that point, Portas had never considered a relationship with a woman — ‘I certainly wasn’t a suppressed lesbian,’ she later reflected — and insists her love for Rickey took her by surprise, adding: ‘She gives complete love to the world and it is the most refreshing, beautiful thing.’
Rickey, too, had not come out as gay before meeting Portas. But their relationship quickly became both public and serious, making them Britain’s most high-profile lesbian couple.
The pair had a civil ceremony in 2010 and embarked on IVF the following year, with Melanie to carry the child as she was the younger woman.
They were among the first same‑sex couples to convert that partnership into marriage on December 9 last year when Portas took Melanie for dinner and then surprised her by heading to Westminster Register Office at midnight, where their family and Horatio were waiting for them.
Today, they share a £5 million home in London’s Primrose Hill with Portas’s eldest children, Mylo and Verity. Portas’s ex-husband, the first person she told about Melanie, is a regular dinner guest. Melanie also spoke out this week about the unusual circumstances surrounding Horatio’s birth, insisting that she had no qualms about Portas making it public.
‘Gay people are getting married and they are having children, so I don’t believe there’s a downside to sharing the information,’ she told The Observer.
‘We are simply sharing something which feels very normal to us all as a family, and if it inspires people or makes them think differently — or even if it changes their perception of ‘normal’ — then that can only be positive.’
But while Horatio’s legal mother is the UK’s leading retail and branding expert, his biological father is rather more low-key.
Despite embarking on a career as a police officer, more recently he has worked as a bar manager for his eldest brother, successful entrepreneur Michael Newton.
Indeed, Portas and her siblings remain close and highly protective of each other.
While Lawrence has worked for his eldest brother, he lived for several years with another brother, Joe, in North London.
For the past three months, he has been living with Portas, Melanie and their children at her stunning London home, where toddler Horatio addresses each in turn as Mama, Mummy and Daddy Lawrence.
But Lawrence is about to emigrate to Bermuda to start a new life there with his girlfriend.
Portas, who says she watched her brother struggling for years after their mother’s death, says that while she coped by taking control and trying to micro-manage everything, Lawrence ‘ran away’ and ‘became the hedonist’ later in life.
And the anger she felt as a child only grew as her own children grew up. This week she recalled: ‘I’m looking at these two kids and thinking: ‘Jesus! That was me coming home to do all the cooking. That’s you, Lawrence. This is just criminal.’ And I grieved for this 14-year-old boy — and I suppose I grieved for the 16-year-old girl that I was.
‘I didn’t have a life for five years. It was a grey world, a very grey world.’
But the rage she once felt towards her father, who died suddenly of a heart attack in the same year he remarried and left everything to his second wife, has softened thanks to several years of therapy, not to mention the birth of Horatio.
Referring to her book, she said: ‘With all the trauma in there, this is a beautiful, happy little world.’
In an extract of her autobiography Shop Girl, published in The Times this week, she uses the present tense when she recalls the existence that she and Lawrence carved out together as teenagers alone at home without an adult to guide them.
‘Together we have created our own way of being,’ she writes. She might just as easily be describing the present. For while the choices she has made might seem unconventional, it seems clear that after years of private anguish, Portas has fought her own way towards a happy ending, one which has very much included the beloved younger brother she always vowed to take care of.
