Grandpa's favourite photo: Prince Charles releases a black and white portrait with Prince Louis that sits pride of place in his drawing room at Birkhall to mark his grandson's second birthday

• Prince Charles, 71, shared an adorable photo to mark grandson Louis' birthday
• The unseen snap shows Charles cradling the young prince to his chest
• It is not known when the photo was taken but it appears to be in a royal garden 

Prince Charles has released an unseen photo with Prince Louis to mark his grandson's second birthday today. 

The adorable black and white snap shows Charles smiling as he holds Louis to his chest. The young prince wraps his arms lovingly around his grandfather's neck. 

The photo is clearly a favourite of Prince Charles as it sits pride of place among a collection of treasured family snaps in the drawing room at Birkhall, his home on the Queen's Balmoral estate. 

Prince Charles has released an unseen photo with Prince Louis to mark his grandson's second birthday today. The adorable black and white snap shows Charles smiling as he holds Louis to his chest. The young prince wraps his arms lovingly around his grandfather's neck

The photo was shared by the Clarence House Twitter account this morning, pictured

It was shared on the official Clarence House Twitter account this morning with the caption: 'A very happy birthday to Prince Louis, who turns two today. The young Prince enjoys a hug from his grandfather the Prince of Wales.' 

It is not known when the photo was taken but it appears to be at an informal family gathering as Prince Charles is in short shirt sleeves. The background of the photo suggests it was taken in the garden of one of the royal residences. 

The portrait, which might have been taken by the Duchess of Cambridge, a keen amateur photographer, could be seen in the background of a photo released earlier this month showing the prince opening London's Nightingale Hospital via video link. 

The photo is thought to be a favourite of Prince Charles as it has pride of place among a collection of treasured family snaps in the royal's Scottish home of Birkhall, on the Queen's Balmoral estate. The photo is seen on top of the piano behind Charles, pictured

The Duke and Duchess of Cambridge also shared photos of their youngest son to mark his second birthday.

Taken at Anmer Hall, their Norfolk home, this month by his doting mother Kate, they show that Louis is growing up fast.

Gone are the little wisps of baby hair and chubby face we have been used to seeing.

Instead he is now a proper cheeky little boy, full of life just like his brother, Prince George, six, and sister, Princess Charlotte, who will turn five next month. 

Adorable: With his little hands smudged with paint and a broad grin on his face, Prince Louis is clearly pleased with his artistic creation

The young prince raised his rainbow coloured hands to his face, that were carefully painted on him by his mother Kate

Supporting the NHS: These charming pictures show that – just like millions of other children across Britain – his parents are keeping him busy by painting rainbows to celebrate the NHS.

Gone are the little wisps of baby hair and chubby face we have been used to seeing. Instead he is now a proper cheeky little boy, full of life just like his brother, Prince George, six, and sister, Princess Charlotte, who will turn five next month

As we can see Louis, dressed in a blue checked shirt, also loves his arts and crafts – one of Kate’s favourite things to do with her children – and has no fear of getting his hands dirty.

He looks positively ecstatic to be getting so covered in paint as he makes a rainbow patterned handprint to stick up on the front window of the family home.

Pictures of rainbows started springing up up in windows across the country after schools closed in response to the coronavirus outbreak.

Prince Louis looked absolutely thrilled with his rainbow coloured handprint to stick on the front window of the family home in Norfolk