The Duke and Duchess of Cambridge have wished Meghan, Duchess of Sussex, a happy birthday

The post read: "Wishing a very happy birthday to The Duchess of Sussex today!", and a cake and red balloon emoji was added to the end.

The note was accompanied by a picture of Meghan - who was known as Meghan Markle before tying the knot with Harry in May 2018 - on a royal engagement at Broom Farm Community Centre in Windsor in November, days before the couple left for their getaway in Canada.

Meghan - who has 14-month-old son Archie with Harry - can be seen holding hands with a little girl with a cupcake in her hand.

Harry's grandparents, Queen Elizabeth II and Prince Philip, have also posted their own message to Meghan.

On the Royal Family's official Instagram account, a photograph of the 94-year-old monarch and Meghan on a visit to Chester in 2018 was shared.

The picture was captioned: "Wishing The Duchess of Sussex a very happy birthday!

"The Queen and The Duchess of Sussex during a joint visit to Chester in 2018."

Meanwhile, Meghan's birthday comes ahead of the release of the new book, 'Finding Freedom: Harry and Meghan and the Making of a Modern Royal Family', on August 11 which was penned by veteran journalists Omid Scobie and Carolyn Durand.

Among the revelations in the tome, include claims relations between Harry, 35, and his brother William, 35, reportedly cooled after the latter advised him not to rush into getting serious with Meghan, saying: "Take as much time as you need to get to know this girl."

According to 'Finding Freedom': "In those last two words, 'this girl', Harry heard the tone of snobbishness that was anathema to his approach to the world. During his 10-year career in the military, outside the Royal bubble, he had learnt not to make snap judgements about people based on their accent, education, ethnicity, class or profession."

Earlier this year, Harry and Meghan quit as senior members of the Royal Family, moved to Los Angeles with their son and signed a deal for speaking engagements through the Harry Walker Agency.