MARIEME and Ndeye were not expected to survive for more than a few days when they were born.
Now aged seven, they are thought to be the only growing conjoined twins in Europe.
While both girls have their own unique personalities and moods, they rely on each other to survive.
“When you are told from the beginning there is no future, you just live for the present,” said their dad, Ibrahima.
Conjoined twins are rare, representing about one in every 500,000 live births in the UK.
Around half are stillborn, with another third dying within 24 hours of birth.
So seeing Marieme and Ndeye celebrate their seventh birthday with a classful of friends doesn’t just give Ibrahima joy, but also to the doctors who have cared for them.
Marieme and Ndeye share one pair of legs and one pelvis but each has a spinal cord and a heart.
They have round-the-clock care but go to a mainstream school in south Wales with their friends.
“They are fighters and proving everyone wrong,” said Ibrahima.
“My daughters are very different. Marieme is very quiet, an introverted personality, but it’s completely different with Ndeye, she’s very independent.
“I would not pretend it’s easy but it’s a huge privilege. You feel lucky to witness this constant battle for life.”
When the twins were born in Senegal in 2016, their parents had been expecting one baby. Doctors didn’t expect them to live much longer than a few days.
“I was preparing myself to lose them very quickly,” Ibrahima told the BBC’s Inseparable Sisters documentary.
“The only thing we could do is be beside them and not allow them to walk alone through this journey. We saw very clearly early on that we were dealing with warriors, who hang on to life.”