Shawn Mendes has joked that his own mum leaked details of his secret journal during a recent event called "An Evening With Shawn Mendes" at L.A.'s Grammy Museum.

In a Q&A with moderator Scott Goldman, the singer discussed everything from growing up with his fans to never taking his success for granted.

When chatting about single ‘Nervous’, the 20-year-old said: “I'm the most nervous guy. Really, what I started to realize is that when you get nervous around people, when you get nervous on stage, it genuinely means you care. And the second you stop getting nervous is maybe when there's a problem, you know?

“So, I really take nerves to heart. Nerves mean that there's something inside thinking like you need to care about this."

Fans especially loved the interviewer bringing upShawn’s secret journal: "Wow, how did you know this?" the singer replied. "Did I say this in an interview?!" only for Scott to admit: “I have my sources.”

That resulted in Shawn immediately pinning the blame on family member, saying: "Is it my mom? The 'Truth Is' journal...I know what you're talking about. So, I have a journal, and in the journal, I basically go, 'Truth Is...' And I write everything that's true.

“And I think a lot of the times we lie to ourselves about life and how we feel about people or about things, and I go—no matter how crazy or how obscure this thought is—I go, 'The truth is, this is how I feel about this.' And that's what I have."

He joked: “And I'll never tell you what's inside,” before adding: "I can't even believe you know that exists. You must've emailed my mom!"