5 Seconds of Summer frontman Luke Hemmings and songwriter Sierra Deaton have welcomed their first child together. “Written and Produced by Sierra and Luke Hemmings.”The insight is not only rare but reluctant. In 2020, Hemmings tweeted, “People need to be more aware what their words can do to others mental health. “Me and Sierra are very, very private,” Hemmings told Rolling Stone last year. Earlier this summer — after he almost accidentally leaked the news in the acknowledgements of his debut solo album Sidequest — the couple announced that they’re currently expecting their second baby, another daughter.