Identical twins, thought to be among the most premature ever recorded in Britain, have been described by their parents as "little miracles".
Imogen and Annabelle Weir were born at just 23 weeks and four days, weighing about a pound each.
They spent four months in hospital enduring blood transfusions and emergency surgery.
The girls have now been settling in at home in Paisley in Renfrewshire with their parents Claire and James.
They have been supported by the Twins and Multiple Births Association (Tamba) who said the fact that the twins were born so early but have gone on to do so well was "truly incredible".
They were born three days under the 24-week legal limit for abortion in the UK.
The girls were born last April, more than three months early.
Mrs Weir, 31, said: "They are the youngest and smallest surviving twins to be born in Scotland.
"I'd never heard of twins so small surviving. It didn't seem possible for one, let alone two.
"The consultant told us that if the girls had been born just two years ago they wouldn't have survived - that's how fast medical technology is advancing.
"They have surprised everyone. They will always be our little miracles."
'Filled with worry'
Mr and Mrs Weir met at university in Dundee nine years ago and married in 2013.
Mrs Weir was given an early scan and the couple were told that there were two strong heartbeats.
Mr Weir, also 31, added: "We don't have a history of twins as a family, so it was a shock.
"We were over the moon and pretty overwhelmed."
Mrs Weir's 20-week scan showed the twins were growing well, but just a fortnight later, at 22-and-a-half weeks, her waters broke.
She was taken to The Royal Alexandria Hospital in Paisley before being transferred to the Princess Royal Maternity Hospital in Glasgow.
She said: "I was just trying to keep the babies inside me for as long as possible. It was a really horrible time, filled with worry.
"After 23 weeks, they would at least have a chance of resuscitation so I hoped they would stick in there. Each day brought more hope.
"I got to more than 23 weeks but then I got very ill with a sepsis infection and they had to induce me. The fact that they were twins, that I had an infection and they were so premature all lowered their chance of survival.
"I didn't have a lot of hope."
'Fitted in one hand'
The twins were born in the early hours of 3 April.
Mrs Weir said: "They were whisked away to intensive care - I didn't even get to see them.
"I got to hold Imogen after about six days but Annabelle was smaller and more vulnerable, so I didn't get to hold her for a few weeks. They were so tiny they fitted in one hand."
The girls still weigh only 11lbs and 12lbs and have to wear 0-3 month baby clothes.
"It was a terrifying experience but wonderful to be at home now as a family," Mrs Weir added.
"Now we are experiencing all the normal struggles new parents have but we have loved every minute. We know how lucky we are."
Helen Peck, Tamba's Scottish co-ordinator, said: "We are delighted for Claire and James and the twins. Imogen and Annabelle's story is just remarkable.
"They are truly incredible - a pair of miracles.
"To see premature babies born this early and go on to do so well is incredibly rare. It is a testament to the wonderful medical staff that they are now growing well."
Learn more about Imogen and Annabelle's story on BBC ALBA's Scotstar: Teasairginn Eiginneach, available on the BBC iPlayer until Friday, 3 February.