The Duchess of Cambridge was a hard-working and conscientious student who excelled at sport, her former teachers said after surprising her on a royal visit in Wales.

Denise Evans-Allford and Kevin Allford drove from their home in Carmarthen to the Mumbles, where Kate and the Duke of Cambridge were visiting on Tuesday.

They had not seen Kate, now 38, since she visited brother James with sister Pippa at St Andrew’s prep school in Pangbourne, Berkshire, when she was 14.

Kate was already a pupil at the school when the couple arrived there in 1990, with Mrs Evans-Allford teaching PE and her husband teaching French and German.

After hugging her former teachers, Kate told them: “I want to instil in my children the life I had at St Andrew’s”.

The couple moved into a school flat at St Andrew’s, where Kate and her friends would visit the couple and their young daughter Angharad.

“Catherine and her cohort used to board in their final year,” Mr Allford said.

“They boarded in the week. It was good to start the day pupils boarding before they went to boarding school.

“Catherine and her friends used to come to our flat after prep.

“Our daughter was only one or two then and they would come and entertain our daughter.”

He said some girls at that age could be shy but Kate was confident speaking to both adults and children.

Both teachers described how happy Kate had been during her time at St Andrew’s.

“She had such a wonderful time,” Mr Allford said.

He enjoyed teaching Kate’s class so much that he asked the headteacher if he could continue to do so for another year, to take them through their entrance exams.

“That was a hard-working year for them,” he recalled.

“But she was a hard worker and very conscientious. Obviously she was the same in sport.

“She was a tremendous athlete and swimmer. I used to be in charge of swimming and she was very, very good, as her sister was.

“Carole was sporty too. Denise played on a netball team socially with the parents and Carole did that for a while.”

The Duke and Duchess of Cambridge visit south Wales
The couple taught Kate at a school in Berkshire (Arthur Edwards/The Sun)

Mr Allford described how parents at St Andrew’s played an active part in their children’s education and often attended sports matches and functions at the school.

“A good prep school is like a big family,” he said.

The couple have kept in touch with fellow pupils and teachers, who have been in touch after news of their meeting with Kate emerged.

They had driven to the Mumbles from their home an hour away early on Tuesday morning and waited outside Joe’s Ice Cream Parlour to see her.

After waiting for an hour, they saw William and Kate’s car driving past on the way to the RNLI’s Mumbles lifeboat station, which they visited first.

The couple decided to go for a coffee nearby to warm up and returned to find the couple inside the ice cream parlour, with a large crowd gathered outside.

The Duke and Duchess of Cambridge visit south Wales
The Duke and Duchess of Cambridge during the visit to Joe’s Ice Cream Parlour (Arthur Edwards/The Sun/PA)

“Denise called a security officer over and said, ‘Please, if you can contact her, tell her that Denise and Kevin Evans-Allford are outside and would love just to say hello’,” Mr Allford said.

“He said, ‘Well, the duchess is very, very busy’.”

The couple decided to write a note in the hope it could be passed to Kate so she could contact them in the future.

They wrote it on the back of a postcard featuring Six Nations fixtures and wrote: “Much love, Denise and Kevin Evans-Allford” along with their address and a kiss.

“The security officer very kindly took that back into the ice cream place and then somebody came to find us,” Mr Allford said.

“She said, ‘Follow me’ and she put us right next to the doorway. We really want to thank that security officer.”

At the end of the visit, Kate came out of the ice cream parlour and approached the couple, telling them: “It’s such a small world”.

“We didn’t know what to expect when she came out, we didn’t want to break protocol,” Mr Allford said.

“We wouldn’t feel right curtsying or shaking hands. We didn’t have to do anything in the end because she instigated a hug right away.

“She has obviously changed physically since we last saw her, she has grown about a foot but in terms of personality and the way she is, she hasn’t changed at all.

“It was a great occasion for us, it was a very emotional reunion.

“After she left us, she got in the car next to William and said, ‘They’re my former prep school tutors’, and he said, ‘Oh, wow’ and made a special effort to wave at us.”