Rosie and Ruby Formosa, who were born conjoined at the abdomen and shared part of the intestine, are celebrating their first birthday.
The identical twins, who celebrate their first birthday today (Friday, 26th July), underwent an operation at London's Great Ormond Street Hospital the day after they were born.
Despite being told that survival chances were low, the sisters are now doing well and are 'very happy and bubbly', according to proud mum Angela, 32, from Bexleyheath, south London.
"It was quite a tough journey, really. It's quite emotional thinking back, thinking what we must have been going through at the time. It was really tough," she told reporters.
"Every time we went for a scan, we were worrying whether there was still going to be a heartbeat.
"They weren't making any plans to give birth to them. All of a sudden it was like 'OK - we need to make a plan because they're still here, they're going to arrive, so now we need to make plans and where we will deliver and where we will go'."
Angela and husband Daniel, 37, didn't think the girls would make it to their first birthday
"When I was pregnant I couldn't see us getting this far. I was taking each day as it came. I am over the moon. It's so lovely seeing them doing normal things and being happy when you didn't even expect to have them," she said.
They're crawling around, trying to stand up on all the furniture and they're playing with toys and taking toys off one another.
"They're very bubbly, very happy, they are very determined - but we knew that from the start really.
"They've never really been apart so I don't know whether they're inseparable or not but they'll play independently and then they'll look for one another."
Angela said she had a 'textbook' pregnancy with her first daughter Lily, now aged five. Doctors discovered that the twins were conjoined when she was around 16 weeks pregnant.
The girls were delivered by Caesarean section at 34 weeks at University College Hospital. Within a couple of hours of birth they were taken to GOSH for emergency surgery because of an intestinal blockage.
The renowned children's hospital is one of the most experienced centres in the world for the treatment of conjoined twins - but even still they only see an average of one case each year.
Consultant paediatric surgeon Ed Kiely, who was part of the team who operated on the girls, said: "We see perhaps one set of twins a year on average. They're not that rare but because of antenatal diagnosis they don't always get born.
"Even if they get born, two-thirds of them are stillborn or die very quickly because of cardiac problems. For conjoined twins in general, survival chances are quite low.
Conjoined twinning occurs in one in every 50,000 or 60,000 pregnancies in Europe. And about one in 200,000 (of all) deliveries is a conjoined twin with the chance of survival.
He said the hospital is happy with the progress the girls have made and is delighted they are now celebrating their first birthday.
The twins will need regular check-ups throughout childhood once or twice a year.
More on Parentdish: The amazing moment twin boys see each other for the first time