James Corden and Harry Styles have Louis Tomlinson's late mum to thank for their close friendship.
Johannah Deakin, who passed away from leukaemia in 2016, asked James if he could take Louis under his wing while he was filming on The X Factor.
Louis' mum knew the Gavin and Stacey star as she'd once worked as a chaperone on one of his shows.
James told People magazine: "[She] wrote me an email one night saying, 'My son's down in London. I don't know if you remember me. You met him years ago. We're slightly worried that he's in London on his own. Would you reach out to him?'"
"And I said, 'Sure,'" he recalled.
Louis was just 18 when he was grouped together with Niall Horan, Liam Payne, Zayn Malik and Harry Styles - who is now a close pal of James.
"Various members of that band would come around to our house in North London and we'd eat pizza and play PlayStation and my wife [Julia] would feel like she was babysitting," he said.
Speaking of his relationship with Louis, he said: "And then from then on, our friendship has grown, and I love him very, very much. I'm very proud of him and protective of him, always."
In the years since One Direction took the music industry by storm, Harry has been a regular guest on the Late Late Show and even stood in for him when his baby was born.
After the release of Harry's third album Harry's House, he and James teamed up to make a music video for Daylight - on a $300 budget.
The pair crashed an apartment in Brooklyn, surprising the residents.
"They had no idea," Corden said, referencing the girls that were in the apartment. "They certainly had no idea that it was going to be me. They certainly had no idea that Harry was going to be there."
Fans recently noticed that Louis and Zayn may have made amends after their ongoing feud.
The pair had a heated Twitter exchange in 2015, shortly after Zayn left the band.
Louis told The Zach Sang Show: “You’d have to ask him. I could be wrong, but I believe I said, when you asked me a similar question [last time]… I believe I said I don’t think I’m mature enough to get over what’s frustrated me in that relationship.”
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He added: “I don’t know if I’m mature enough now, but I’m definitely closer to being over all that.”
"There's been numerous times over the last couple of years where I've thought about him and hoped he's alright," Louis went on, adding he's "tried to get in touch" with Zayn.
"But it's hard," he said. "I definitely wish him well."
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