Princess Marie-Chantal of Greece pays sweet tribute to her 'number one' husband Prince Pavlos as he marks his 57th birthday with low-key family celebration

The Greek royals looked in high spirits as they gathered in London to celebrate Crown Prince Pavlos' 57th birthday this week. 

His wife Princess Marie-Chantal, 55, shared the snap on social media which featured the couple with three of their four children, Olympia, Constantine and Aristides.

Pavlos is the eldest son of Constantine II, the former King of Greece, who died at the start of last year and he is also the godson of King Charles.

The family were all smiles and looked relaxed as they posed around a table with a lavish birthday cake in the centre. 

She captioned the picture: 'A little birthday celebration with our London lot. Happiest birthday to my numéro uno!' 

Crown Princess of Pavlos cut a relaxed figure in a birthday snap with this wife Marie Chantal, daughter Olympia and sons Aristides and Constantine-Alexios (right)

The family were all smiles and looked relaxed as they posed around a table with a lavish birthday cake in the centre in London. Pictured (L-R) Olympia, Aristides, Prince Pavlos Princess Marie-Chantal and Constantine

The family was dressed casually, with Prince Pavlos donning a casual blue shirt and his wife Marie-Chantal opting to wear a khaki button up blouse with a pair of jeans. 

Their 27-year-old model daughter Olympia appeared to go makeup free and beamed for the snap in a simple black t-shirt and green trousers. 

Constantine sported crisp white striped shirt and grey cargo trousers while his brother Aristides opted for a simple slate-coloured jumper. 

The family are based all around the world. Olympia lives in Notting Hill, Pavlos and Marie-Chantal spend most of their time in New York, Aristidis also lives in the US and Constantine often flies between American and the UK. 

Constantine dated Cara Delevingne's sister Poppy, but the couple split last year, according to Emily Prescott. 

A source close to the couple - who had a 12 year age gap - says it was entirely amicable, adding: 'They are just at different stages of their life. There is no animosity.' 

Royal fans rushed to the comments to wish Prince Pavlos a happy birthday, with some commenting on how happy they looked to be reunited. 

 One wrote: 'What a beautiful photograph.'

Another penned: 'Happy birthday Pavlos, we love you!'

Queen Anne Marie of Greece with Crown Prince Pavlos of Greece and Crown Princess Marie-Chantal of Greece at the Coronation of King Charles last year 

Royal fans rushed to the comments to wish Prince Pavlos a happy birthday, with some commenting on how happy they looked to be reunited

A third said: 'Happy birthday! May all your wishes come true. Love from Greece!!!'  

 A fourth commented: 'Happiest birthday! Beautiful photo... happy family.'

At the start of the year, Pavlos said he would like to change his surname back to 'of Greece'. 

Currently the family is recognised as 'of Glucksburg', relating to their Spanish and German heritage, rather than their Greek one.  Greece abolished its monarchy in 1973.

Pavlos - who is also a member of the Danish royal family - has no immediate German heritage.

In an interview with Greek television channel ERT, he said: that 'My last name has always been that, 'from Greece'. Why do I have to change it? When that law was made it was only to attack us.' 

Glücksburg is a Danish castle which was conquered by the Germans during World War II. 

Pavlos - who is also a member of the Danish royal family - has no immediate German heritage.