Dressed in identical outfits and smiling sweetly for the camera, it's hard to believe these healthy twin toddlers were not expected to survive. Rosie and Ruby Formosa, two, from Bexleyheath in south east London, were born joint at the abdomen sharing the same intestines and a team of 15 doctors spent five hours separating the pair. A life-threatening blockage meant they were transferred to Great Ormond Street Hospital  for emergency surgery but almost three years on and the identical twins are fighting fit. Scroll down for video . Family: Angela and Daniel Formosa with twins Ruby (front left) and Rosie (front right) and sister Lily, seven . Their mother, Angela Formosa, 34, says the girls have been almost inseparable since they were detached from each other in July 2012. She said: 'Wherever they are, they need to know where the other is. Even at nursery surrounded by all their little friends, they are constantly looking to see where the other one is. 'If I'm getting Ruby dressed first, Rosie will run off, find the exact same outfit and pester me until I dress her exactly the same. It's been like that ever since we brought them home. 'They used to crawl around the house chasing one another. Normally Rosie will learn something first - like talking - and within a week Ruby will have caught up - they're just little copycats really.' Mrs Formosa was only 16 weeks pregnant when a scan revealed to her and taxi-driver husband, Daniel, 39, that the twins were conjoined. Together: Ruby and Rosie, who were born with the same intestine in July 2012, are 'inseparable' The couple, who also have a seven-year-old daughter, Lily, prepared themselves for the worst as doctors gave the girls a small chance of survival as they couldn't definitively see where the connection was. Conjoined twins occur every 200,000 births, however, as few as five per cent of those births actually survive being born. Mrs Formosa, a full-time mother, said: 'Hearing the girls were conjoined was the shock of our lives. 'I'd heard of it, but I never expected it to happen to me. I was nervous the whole way through the pregnancy but tried to shut it to the back of my mind. 'When I heard their two little cries when they were born, the worry subsided, but only for a while.' Almost immediately after being delivered by caesarean section at University College Hospital, London, Rosie and Ruby were whisked off to Great Ormond Street Hospital to be operated on. They were delivered at 34 weeks and weighed 5lb 3oz each and the following day they were operated on to clear a life-threatening intestinal blockage. 'Those were the most difficult 24 hours of our lives,' Mrs Formosa added. 'Having my babies taken off my almost immediately after they're born and not knowing if either would survive was heartbreaking. 'When the doctors came out to say the surgery had been a success and that the girls were both fine, it was like the world had been lifted off our shoulders. Complications: Rosie, left, and Ruby, right, were born joined at the abdomen and shared part of the intestine . Sisters: The girls spent a few weeks in hospital before returning home to be with their big sister Lily (centre) 'Seeing their little bodies in two separate cots, instead of one, I just burst into tears. I was so happy.' Mrs Formosa and the girls spent another four and a half weeks in hospital to make sure they were healthy enough to go home. The couple say that even when they were given the all clear they still weren't full prepared to bring both girls home so everything was a 'bit last minute'. 'On the drive back we had to buy bottles from Boots. During the pregnancy I couldn't see us getting to the point where both our little girls would survive.' Toddlers: The identical twins love to dress in matching outfits (left) and playing on their scooters (right) The girls go to nursery five days a week and their recent report card says they are 'getting on just fine' The girls only had a small chance of survival as few as five per cent of conjoined twins' births actually survive being born . Occasionally Rosie and Ruby, who attend nursery five days a week, have to have routine operations, but even those minor setbacks aren't stopping their development. Mrs Formosa said: 'They've both developed as any "normal" child does. We were always a bit worried that them being conjoined could delay that, but it doesn't seem to have done. 'Their report card from nursery says they are getting on just fine. The only problem we have is that Rosie and Ruby keep doubling up on their big sister Lily so they can steal her toys.' Birth: Rosie (left) and Ruby (right) were delivered at 34 weeks and weighed 5lb 3oz each and the following day they were operated on to clear a life-threatening intestinal blockage . Celebrating their first year: Ruby (left) and Rosie (right) are pictured on their first birthday in July 2013 . Today: Rosie (left) and Ruby (right) are fit and healthy two-year-olds and love to double up on their big sister . Conjoined twins are two children physically connected to each other at some point in their bodies. The lowest odds of this happening are 200,000 to one for every live birth and around 70 percent of conjoined twins are female. Conjoined twins are always the same sex and the form of conjoined twinning refers directly to where they are joined. The most most frequent are horacopagus (heart, liver, intestine), omphalopagus (liver, biliary tree, intestine), pygopagus (spine, rectum, genitourinary tract), ischiopagus (pelvis, liver, intestine, genitourinary tract), and craniopagus (brain, meninges). (American Pediatric Surgical Association) Experts think that conjoined twins come from a single egg that fails to separate. Around 200 conjoined twins are born each year and around half die before their first birthday. Veena and Vani, ten, were born joined at the head, but their parents left them in their local hospital in Hyderabad, India because they could not pay their medical expenses. For eight years the girls have eaten, played and slept in one room at Niloufer Hospital and have been cared for by nursing staff. They cannot be separated. Their doctor, Dr Narendra Kumar, a paediatric surgeon, is trying to find an international surgeon who specialises in neurology to perform the operation. He said: 'It has always been possible to operate on the girls because they both have individual brains. 'The problem lies with the one main blood vessel they share so it does have its risks.' Laleh and Ladan Bijani caught the attention of the world when at the age of 29 they decided to have surgery to separate. The sister's skulls were joined above the ear but each of their brains was intact. They were never able to look into one another's face without the aid of a mirror. Their dream was to walk out of Raffles Hospital in Singapore and walk in opposite directions. Sadly they both died after their surgery. Born in Tehran in 1974, they developed different personalities and made separate groups of friends. Ladan was the stronger personality and was more talkative, while Laleh was quieter. So when Ladan said she was determined to become a lawyer, Laleh had no choice but to study law with her. Conjoined twins Shivanath and Shivram Sahu caused quite a stir when they were born in India, with some people in their village worshipping them as divine incarnations. And while one doctor has said that it would be possible to separate the 12-year-olds, who were born joined at the waist, the duo are determined to remain together. Shivram said: ‘We don't wish to get separated. We will stay like this even when we grow old. We want to live as we are.’ The pair, who were born in a tiny village near Raipur in central India, share two legs and four arms and work in tandem to get around. They have stunned doctors with their ability to wash, dress and feed themselves. A local doctor told the family they were both healthy but he could not separate them. They are believed to share the same stomach but have independent lungs, hearts and brains. With practice they have learned to do all their basic daily chores with minimal fuss, including showering, eating, getting dressed and combing each other's hair. They are able to walk down the stairs of their simple split-level home and even run on all six limbs to play cricket and other games with neighboring children.
Rosie and Ruby Formosa were born sharing the same intestines in 2012 . Team of 15 doctors spent five hours separating them in emergency surgery . Now almost three years on the identical twins are fit, healthy toddlers . Mother Angela Formosa, 34, said they're still 'inseparable' after operation . Five per cent of conjoined twins survive birth so family prepared for worst .