Shawn Mendes was an "annoying little brat" as a child.

Asked what piece of advice he would give himself if he could go back in time, he told BANG Showbiz at We Day UK: "I'd probably tell myself to shut up sometimes and stop being such an annoying little brat and be thankful to your parents because they do so much for you ... And I would have told myself to start playing guitar a lot younger."

The singer-songwriter - who has a whopping 2.74 million Twitter followers - revealed his dedicated fans often have the same strange request for him when he meets them at events.

Quizzed on what the craziest thing a fan has ever asked of him is, he shared: "They're always asking me to jump on my back and carry them around which is really bizarre. I'm not really sure why they do that but it's something very regular."

Meanwhile, the Canadian heartthrob admits he's not worried about being criticised for being a bad influence on his millions of young fans as he strives to be a good role model.

He added: "Personally, I don't worry about it because I'd like to think that I'm a good role model and I think it's all about making sure that you are a good role model, especially as you get bigger."

Shawn was attending We Day UK at The SSE Arena in London which celebrates the potential of young people to implement positive local and global changes. The event was attended by 12,000 students and teachers from more than 550 schools in Britain.

Other celebrities in attendance were Sir Richard Branson, Conor Maynard, Martin Sheen, Natalie Imbruglia and Princess Beatrice.