They've been pictured together on several occasions since late 2017.

It's been a busy year for 5 Seconds of Summer, with their single Youngblood spending an impressive 46 weeks on the Billboard Hot 100.

They made a spectacular comeback last year with their Youngblood album and are currently promoting their new single, 'Easier'. 

They may have been dating since 2017, but Ashton Irwin and Kaitlin Blaisdell still appear to be in the throes of newfound love.

The Australian musicians of 5 Seconds of Summer have been friends since they went to high school in New South Wales. And on Thursday, Ashton Irwin and Callum Hood got coffee together in LA.

It's been a busy year for 5 Seconds of Summer, with their single Youngblood spending an impressive 46 weeks on the Billboard Hot 100. 

5 Seconds of Summer's Michael Clifford politely says performing at the ARIAs was 'more exciting' than the Billboard Music Awards...seconds before he clears his throat

The 23-year-old bassist appeared to have no qualms about playing seventh wheel as he arrived for the group date at Double Bay venue The Golden Sheaf.

5SOS' Calum Hood, 23, and Ashton Irwin, 24, attended the Sydney premiere of Muriel's Wedding The Musical on Thursday.

5 Seconds Of Summer bassist Calum Hood, 23, famously landed himself in hot water when he was pictured smoking a cigarette outside a petrol station in January 2015. 

Calum Hood is the only member of ARIA award winning Aussie pop group 5 Seconds of Summer who is single. 

 5 Seconds of Summer frontman Luke Hemmings just celebrated his 23rd birthday, taking to Instagram to thank fans for the sweet messages

He's been hard at work recording 5 Seconds of Summer's fourth studio album.

Five Seconds Of Summer have already dropped three singles from their upcoming fourth studio album. And on Monday, 5SOS singer Luke Hemmings confirmed the band's new album is done.

The members of 5 Seconds of Summer played a risky game of Tattoo Roulette on The Late Late Show with James Corden on Friday.

They're the ARIA Award-winning rockers with millions of fans across the world. 

Zayn Malik's family have been celebrating Martin Tiser's 18th birthday, weeks after he married the One Direction star's sister Safaa, 17.

He's the drummer with one of the biggest bands in Australia.

They made a spectacular comeback last year with their Youngblood album.

Perry made a grand entrance out of a giant red Christmas tree ornament. She was accompanied onstage by backup dancers dressed as purple gift boxes wrapped in red patent leather bows.

She said 'yes' to marrying 5 Seconds Of Summer guitarist Michael Clifford, earlier this year.

Taylor Swift threw the 'most aggressive holiday party known to womankind,' on Friday evening for her 30th birthday.

They gained worldwide fame after their 2014 hit She Looks So Perfect. And now 5 Seconds of Summer have revealed they've been crashing Taylor Swift's birthday parties for five years.

He has been busy in the recording studio with his band 5SOS in the lead up to their fourth album over the past year. 

5 Seconds of Summer drummer Ashton Irwin kicked off the New Year by working up a sweat.

They are celebrating their four-year anniversary together this week.

Ashton Irwin has lived away from his native Australia for more than seven years.

They performed at the Fire Fight Australia bushfire relief concert on Sunday night. 

He proposed to his model girlfriend Crystal Leigh in July 2019.

The boys from 5 Seconds of Summer have revealed the bucks party they want to throw bandmate Michael Clifford, as he prepares to marry fiancée Crystal Leigh.

5 Seconds of Summer guitarist Michael Clifford proposed to his fiancée Crystal Leigh on a clifftop in Bali last year.

5 Seconds of Summer put on an energetic show for the 75,000 attendees at Fire Fight Australia on Sunday.

It's always sunny in California and 5 Seconds Of Summer star Ashton Irwin took advantage of the stunning winter weather in Los Angeles on Wednesday. 

5 Seconds of Summer drummer Ashton Irwin admitted he was feeling unwell earlier this week on Twitter.

5 Seconds of Summer's fourth studio album CALM has climbed to the top of the charts in Australia and the United Kingdom. 

Ashton Irwin has spoken out after 5 Seconds of Summer's new album, Calm, was 'robbed' of the No. 1 spot on the U.S. Billboard Chart this week. 

The boys from 5 Seconds of Summer have previously been accused by fans of putting on 'fake American accents.'

The Love Island star, 30, who is working on the frontline, stood on his doorstep as he cheered on his hospital in Lewisham at 8pm to applaud the health heroes across the country.

Matt Hancock today lost his cool as he was grilled over the UK government's failure to set out its strategy for easing the coronavirus lockdown.

His official spokesman said today that he was receiving 'updates on the coronavirus response' and spoke to Foreign Secretary Dominic Raab and Matt Hancock, the Health Secretary, yesterday.

The Prime Minister has spent a fortnight at his country retreat, Chequers, after being hospitalised with coronavirus.

The Prime Minister has been informed of the proposals for matches to be played behind closed doors. And Mr Johnson sees the resumption of live sport as key to boosting the moral of the nation.

The veteran soap actor was surprised with gifts at his Wilmslow home by his daughter Verity, 39, and son James, 34, in snaps posted on the soap's official Twitter account on Saturday.

As well as believing that leaving the EU is an 'opportunity' for Britain, Claire Ainsley is an ardent pro-family campaigner.

EXCLUSIVE INTERVIEW BY OLIVER HOLT: When he returned from Rio, Sbihi's rocket trajectory began to flatten. Those astonishing ergo numbers dipped. His struggles became an open secret.

The Prime Minister told aides during a three-hour Covid-19 strategy session that doctors had given him permission to return.

The Prime Minister will return to work in Downing Street on Monday to find restlessness brewing in the Tory ranks for restrictions to be relaxed.

DAN HODGES: When the coronavirus crisis began, Boris Johnson wanted to follow the science. But thanks to the paranoia of the Chinese government, there was little science to follow.

The Labour leader has written to the Prime Minister to urge him to hold an 'adult conversation' with Britons to spell out what they are likely to face next.

Ministers have ordered production of up to 50 million new immunity tests as part of what experts hope will be a 'game-changing' development in the battle against Covid-19.