Hollywood actor Mark Wahlberg, who starred in 'Ted', has offered some words of advice to teenage heartthrob Justin Bieber as he knows how tough growing up in the spotlight can really be.

Back in 2010, Wahlberg offered to rap with the 'Boyfriend' hitmaker who agreed it would be a fantastic duet and he has now told him to behave himself because the media can be brutal in changing people's reputations:

"Justin, are you listening? Don't be so naughty, yeah? Be a nice boy, pull your trousers up, make your mum proud. I was in prison before I got a record out and I don't think he's been to prison. He's a nice enough kid and you're going to be a teenager."

"But if you're being a teen in the spotlight you're going to be criticised for it. This career can be short-lived - you might as well be the best you can while you're doing it."