Reminiscing about the disco room at a seaside family holiday resort they visited as kids (something Olivia had forgotten about while Will enthuses that "it's my first memory of properly hearing music, as in, when you feel it in your bones") and getting sidetracked when a misheard comment switches the conversation from cursive singing to screaming heavy metal, Will and Olivia are here to make music and have fun doing it – and they're inviting you along for the ride.

With a love for playing and performing inbuilt at a young age, writing was something they felt drawn to naturally. "I remember always making things up on the piano and kind of improvising and stuff, but I never actually knew what it was," Will recalls.

For Olivia, her introduction to writing music was quite different. "My dad would go to the shop and buy, like, 'Now [That's What I Call Music!] 92' and all those CDs," she laughs. "I got Taylor Swift." The album not only ignited a lifelong love of pop, but inspired her to pick up a brand new instrument. "I got my first guitar because of her," she grins. "I think it was once we were exposed to the sound world of pop, and more pop genres, that we started to write."

After sharing a series of home-produced singles online alongside existential yet ever-relatable musings like 'did they friendzone u? Coz same' and 'all these emotions man', the band went into the studio for the first time to record their debut EP. Released last year, 'how can i pretend?' is a compilation of songs the siblings describe as being "like a step out of the bedroom for us."

It's a metaphor the band are sticking with as they enter a new chapter. "We're opening the bedroom door to a studio," Will describes. "A lot of our songs are quite..." He pauses, taking a moment to work out the best way to express what he's thinking. "They're relatively melancholic so far," he laughs. "In a live show, you need a balance of those beautiful singer-songwriter songs, but then you also want those really cool bops."

Feeling that they were lacking in the latter, a bop is exactly what they made. Latest single 'Petals On The Moon' is an ode to wanting bigger and brighter and better, forged from the delightfully pure desire to have a song that people can dance to. Recorded from the week after their last live shows in Manchester and London in December, making this single is something Olivia describes as being "the most fun I've had recording a song yet."

From bringing their ideas to life through collage, to compiling photos of their producer's dog ("Teddy's just a legend," Will grins, while Olivia enthuses, "I literally have a whole album of photos of Teddy on my phone: he is the star of the show, he's the 'it girl'"), that time spent in the studio together has instilled Wasia Project with a new lease of life.

Will is quick to agree, saying, "it's a really fun thing to see how a track breaks out of the songwriting room and develops into a whole new song."

"We're opening up this sound we've created, which is kind of a fusion of a whole bunch of different influences," Olivia grins. "I think we're trying a lot of new things." That is as much as she says before caution sets in. "I don't know much I should give away..." With festival appearances set for this summer and more new music imminent (the band's next single is set to drop early April), what we've heard so far is only the beginning.

He's not wrong. At Wasia Project's last live show in London in December, they not only added a trombone player and saxophonist into their ever-growing live band, but also partnered with a local bubble tea vendor to offer free drinks to their crowd. "We just wanted something to give to the fans," Olivia states. "Like, why not?"

Taking to the studio like a duck to water, Wasia Project are entirely in their element. "We're in this new studio space that's basically a playground," Olivia details. "We feel a lot more free than we have ever been." With that freedom, the pair are having the time of their lives. Experimenting with their sound, playing with different genres and textures, working with new instrumentation and sound worlds, the siblings are building the bigger and better that the lyrics of their last single were yearning for.

Experimenting with and evolving their live show wasn't the only reason they set up this partnership. It was also a way the siblings could say thank you and give back to their fans. "There's this really intimate connection we have with the people who have supported us," Oliva says. "It is very early on, and it's very personal, and we want to keep this sort of connection."

The fondness they speak of their fans with is every bit as enamoured and appreciative as the hype that surrounds them online. The band's social media tags are full of devotion. There are dedications, memes, song covers, fan art… A community built around enthusiasm for the music Wasia Project are creating.

This is the world that Wasia Project create not only for their fans but for themselves, and they thrive in it. "We're making a lot more music to release, and we're releasing more music, and we're in the recording studio a lot more," Olivia details of their plans for this year. They aren't sharing the particulars of any further releases yet, but from what they are hinting, it seems clear that it's going to be something special.