Watch Harry Styles sing One Direction’s ‘Stockholm Syndrome’ at Niall Horan’s concert

Bandmates for life.

Harry Styles supported his former One Direction bandmate Niall Horan at Horan’s concert at Co-op Live in Manchester, England on Tuesday.

In a fan video shared on X (formerly Twitter), Styles, 30, was seen singing and dancing in the crowd while Horan, 30, performed the One Direction song “Stockholm Syndrome.”

The “Watermelon Sugar” singer wore a yellow cardigan sweater over a white T-shirt at the concert.

Fans of One Direction – which broke up in 2015 – were thrilled to see the video of Styles on Horan’s show.

One person tweeted, “Wow!”

“I love this ‘H’ showing support for Niall,” another fan wrote.

Another fan asked, “When will the reunion happen?”

Horan is currently on his Show: Live On Tour, which kicked off in Ireland in February. His final show is scheduled for October 9 in Colombia.

The “Meltdown” singer launched his solo career when One Direction took an indefinite hiatus following Zayn Malik’s exit from the group.

The former boy band — consisting of Horan, Styles, Malik, 31, Liam Payne, 31, and Louis Tomlinson, 32 — formed in 2010 under Simon Cowell on the U.K. version of “The X-Factor.”

All five members of the group were teenagers when they came into existence.

One Direction became the best-selling boy band of all time before their disbandment.

Since the breakup, Horan has released three studio albums — 2017’s “Flicker,” 2020’s “Heartbreak Weather” and 2023’s “The Show.”

But it is Styles who has had the most successful solo career so far out of all five 1D alumni.

He came out with his second solo album, “Harry’s House”, in 2022 and then went on his Love On Tour which lasted 22 months until July 2023.

The “As It Was” singer also starred in the films “Don’t Worry Darling” and “My Policeman.”

Despite moving on from One Direction, Styles still showed love for the band that made him famous at the 2023 Brit Awards.

Accepting the award for British Artist of the Year, Styles said in his acceptance speech, “I want to thank Niall, Louis, Liam and Zayn because I wouldn’t be here without you. Thank you so much.”

Two months later, Styles hinted at a One Direction reunion on James Corden’s final “The Late Late Show.”

“I guess I would never say that,” he said.