When Paul Morgan heard that Gavin & Stacey were filming their Christmas special down Barry he knew he had to take his son down to the set.
Paul's son John, who lives in Caerau in Cardiff , was diagnosed with Duchenne Muscular Dystrophy when he was born.
His condition means that he uses a motorised wheelchair and his parents are his carers 24 hours a day, seven days a week.
He can no longer feed himself and he wears an air pipe to his nose to aid with his breathing.
John, aged 20, has always been a huge Gavin & Stacey fan - he even knows every line from every episode in the show.
"He has worn out three box sets, we had to have another one delivered to the house," dad Paul said.
When Paul took John down to Barry last week to watch the cast film, he couldn't believe what happened next.
He said: "We went to Barry the week they were filming, we were in the van and I asked one of the security guards if there was any chance we could see the cast.
"Over the week everyone came over to the van to see John, we couldn't believe it.
"James Corden got into the van and even had his own carpool karaoke with him singing a Christmas song. Ruth Jones also got in the van and she got into the character of Nessa."
"Rob Brydon also took time out to read lines from the first series, John was laughing with him."
As well as meeting the cast, John also had pictures with the stars.
"Each member of cast spent around 10 minutes with John, they didn't have to do that. They must be really busy filming so I can't believe that they took time out to spend time with John.
"John was so excited that he met the cast, we spent 15 hours on set in total," the 54-year-old added.
You can follow John's journey through his Facebook page .
