Funniest photos of the royal family joker, birthday boy Prince Harry

Prince Harry, who celebrates his 34th birthday on Saturday 15 September, has said he'll always have a childish streak. While his fun-loving nature has been tempered by the sense of responsibility he's acquired through his military career, and his sense of duty to the Firm, the Queen's grandson still delights in pranks.

Her Majesty regards this as an asset, perhaps seeing echoes of Prince Philip's penchant for jokes. And the Queen has no hesitation in asking Harry to undertake engagements on her behalf, often sending him on tour to nations where his informal style will go down well.

From joking about his brother Prince William's hairline, to making jibes at the press, Harry has had the nation in stitches for years. Let's take a look a some of his funniest moments…

The youngster took his mother Princess Diana by surprise when he stuck out his tongue at the Queen's official birthday, Trooping the Colour, on the balcony of Buckingham Palace as a child.

"I am who I am. I'm always going to have that little sort of - how do you say? Child streak," Harry, seen here at a charity event with Prince Seeiso of Lesotho, once said.

The royal brothers are incredibly close and William is frequently the butt of his jokes – most of them about his hair loss.

"I think he definitely is brainer than I am, but we established that at school," Harry once said of his older brother. "Along with his baldness."

The Prince, who is great with children, embraced his inner kid as he opened a new playground in Newham, London with former mayor Boris Johnson.

During an Invictus Games event in Toronto, Harry playfully teased a little girl when he noticed her stealing his popcorn.

The former soldier, who served in Afghanistan, dared to challenge Olympic sprinter Usain Bolt during a visit to Kingston, Jamaica.

Harry had been asked especially by the Queen to represent her on a Diamond Jubilee Tour of Belize, the Bahamas, Jamaica and Brazil. Quoting Bob Marley, Harry said: "The Queen couldn't be here. So you're stuck with me … But don't worry cuz every little thing's gonna be alright."

Prince Harry let his hair down and enthusiastically took part in a Mexican wave, alongside his brother Prince William and Harry's then girlfriend Chelsy Davy at the Concert for Diana, 2007.

The Prince photobombs New Zealand officials at the Commonwealth Games in Glasgow, summer 2014, giving two thumbs up and grinning widely behind the unsuspecting men.

Massey University then shared the snap on their Twitter account. "Royal photobomb alert! Prince Harry with our Prof. Emeritus Gary Hermansson at #Glasgow2014," read the caption.

Princes Harry and William pose for a selfie with Jamal Edwards at Buckingham Palace, in the first ever social hub as part of The Queen's Young Leaders in July 2014.

The talented polo player regularly takes part in charity matches for his foundation Sentebale, which he set up in memory of his mother Diana. Here he is pictured gently teasing the opposition.

During a visit to the charity Canine Partners Training Centre, Prince Harry cuddled an eight-week-old puppy called Veyron. The charity teams guide dogs to people with disabilities including injured soldiers - a community that Harry has long supported.