The Prince of Wales receives a card from Oliver Horne, 4, with brother Daniel Horne, 22-months, and their mother Nicola Horne during a visit to Kemble train station in Gloucestershire
The Prince of Wales shared the "great moment" he met his grandson with a schoolboy today - telling him "it's fun to be a grandfather".
His Royal Highness met George Austin, nine, as he opened a new garden at Kemble railway station in Gloucestershire this morning.
George and sister Lucinda, four, were at the station - the closest to The Prince's Highgrove home - with their grandparents.
The Prince attended the station to open a new garden worked on by students at the Royal Agricultural University, of which he has been president for 25 years.
His Royal Highness appeared in a humorous mood, laughing and joking as he met members of the public, staff and designers and unveiled a plaque at the station.
George, who lives in Wimbledon, South West London, said: "I was asking him about the baby and he said it was great meeting him at the hospital.
"He said it was really fun being a grandfather.
"I was really hoping the baby would be called George, it is a great name."
Oliver Horne, 4, waits for the arrival of the Prince of Wales at Kemble train station in Gloucestershire.
George was at the station, a Grade II-Listed building, with grandparents Sue and Peter Skinner, who live in Kemble.
Mrs Skinner said: "It is marvellous that the baby has been born, I think he will make the most fantastic grandfather.
"He was brilliant with these two. Being a grandparent is very special."
The Prince was congratulated on the birth of his grandson, Prince George of Cambridge, by delighted crowds at the station.
He was presented with cards written by Oliver Horne, four, and brother Daniel, 22 months, who wore Union flag hats for the royal visit.
The card read: "To HRH the Prince of Wales and HRH the Duchess of Cornwall. Congratulations on becoming grandparents on the birth of Prince George of Cambridge.
"Love, Oliver Horne, four, Daniel Horne, one."
Proud mother Nicola Horne, 38, who lives in nearby Cirencester in Gloucestershire, said: "Oliver said to him 'Congratulations on being a grandad'.
"Prince Charles said 'Thank you'. I think he was really touched.
"He asked Oliver 'Have you got a granny and grandad?' and Oliver told him he had.
"It was great for the boys to meet him, they love the new baby and were so excited to see him on the television.
"When they came out of the hospital, Daniel was shouting 'More baby, more baby'."
Ms Horne handed The Prince flowers and a soft toy rabbit for the baby.
Full-time mother Philippa Smith, 23, presented son Preston, two, to The Prince.
"I congratulated him on the birth of his grandson," she said.
"He made a few jokes as he walked through with his usual humour.
"It was great to see him on such good form."
The Prince admired the once-derelict garden at the station, which has been redesigned by local company Designspace Outdoors.
Staff and students from the Royal Agricultural University worked on the project, which was started this year after a campaign by local resident Dawn Adams.
Around 15 students have worked on the garden, designed by Sophie Crawford of Designspace Outdoors, since February.
Professor Chris Gaskell, Principal of the Royal Agricultural University, said: "He has double ownership of this project.
"He is pleased because he lives locally and loves bringing old things to life but he is also pleased that it was students from the RAU that put in the leg work."
The focal point of the garden is a dry stone wall, which runs through the middle, and has seats incorporated into it.
Sophie Crawford said: "The Prince knows about gardens and he commented on the skill it takes to build a dry stone wall.
"It was a difficult task but the students carried it off brilliantly."
Flowers in the garden were donated by Dobbies Garden World in Cirencester.
The Prince, wearing the Royal Agricultural University tie, made a short speech after he unveiled a plaque to open the garden, which was finished yesterday.
He said: "I am so thrilled to have this opportunity as president of the Royal Agricultural University.
"I think that the students and everybody else involved in this is enormously encouraging.