In 1969, an unlikely friendship formed between a US soldier fighting in the Vietnam War and an 11-year-old boy in Slough, through a love of football club Queens Park Rangers (QPR).
Nils Guy was 22 and had been in the US for less than a year when he was called up for military service with orders overseas in Vietnam.
When on active duty, he wrote a letter which was published in the QPR matchday programme, asking if anyone would be interested in sending him clippings on how his club was doing.
John Wild, aged 11, responded to the request and started to send Nils match programmes and other Rs' memorabilia.
Nils had emigrated to the US from Surrey, and was called up for military service in Vietnam within a year.
He told Adrian Chiles on BBC Radio 5 Live that he didn't mind being called up so quickly, but the reality of war was still a shock.
"It hit home straight away," he said.
"It's a horrendous feeling going into somewhere that's being bombed, and hearing gunfire and bullets going past all the time.
"I wasn't getting much mail from my parents and it took a long time to get there.
"I asked anybody to send me some memorabilia, just to keep me sane."
Nils said receiving the QPR programme while on the battlefield was an amazing feeling and brought him back to reality.
"I think I was in the middle of a firefight when we got mail and I opened it up and it was like an out-of-mind experience.
"Bullets raining around my head, and here I am reading a programme from QPR - it was fantastic."
Now in his 60s, John recalled seeing the advert as a child and said he thought it would be a nice thing to do.
"At the time I'd just moved house - I'd moved out of Shepherd's Bush, believe it or not - and I didn't really have too many friends at the time.
"And I was still going to QPR with my dad and with friends that still lived in London.
"I read Nils's letter and I just thought I'll pop this guy some programmes and some clippings. I think I sent a couple of badges and some stuff like that.
"I was always seeing things about Vietnam on the TV, so this was just something that interested me."
The pair lost contact after the war, but John was determined to be reunited with his fellow QPR supporter.
After decades of wondering what happened to his pen pal, with the advent of the internet, he finally tracked down Nils.
"I started to look up lists of veterans who had served and I still couldn't find him, but his name was so easy to remember.
"I just stuck it into Facebook one night and there he was. My wife asked what was wrong with me because I got quite tearful.
"I just said 'I've been looking for this guy forever'."
John tentatively asked Nils if he was the same guy who sent a letter to QPR in 1969, and explained he was the 11-year-old who wrote to him.
"He came back and said yes, it's the same guy. It really was a great moment to know that he'd survived."
The pair occasionally talk online, but have never met in person. They spoke together for the first time on 5 Live's Chiles on Friday.
Nils hasn't been back to watch his beloved QPR since moving to the US - he's now based in California.
If they ever get the chance to meet in person, John - who now lives in Bracknell - has made a promise to Nils: "I've got to buy you a beer one day."