Lady Louise Windsor makes a rare public appearance for the Queen’s birthday

Plenty of royal family members were out and about for the Queen's private birthday celebrations over the weekend, but one royal who isn’t often seen in public made a surprise appearance.

Lady Louise Windsor, the 15-year-old daughter of Prince Edward and Sophie, Countess of Wessex, arrived at the Easter Sunday church service in Windsor that Her Majesty attends every year.

The young royal is seldom seen outside of formal royal occasions, as her parents have always focussed on giving Louise and her younger brother James, Viscount Severn, as normal an upbringing as possible.

Fortunately, the Wessexes are some of the less-publicised royals, rarely appearing in tabloid magazines or being hounded by paparazzi, allowing Louise and her brother to grow up relatively privately and out of the public eye.

One of Louise's most public outings was when she acted as a bridesmaid to Kate Middleton at her 2011 wedding to Prince William, 7-year-old Louise looking adorable in her little white outfit.

Louise was born prematurely in 2003 when the Countess suffered a placental abruption and was rushed to hospital for an emergency Caesarean, after which the newborn was transferred to a neo-natal unit in St George's hospital in London to be cared for.

It was a traumatic time for mother and child, with both losing a significant amount of blood during the birth, but they both survived and young Louise grew into the happy and healthy young woman we see today.

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Prince Edward and Sophie chose not to have their children take on the formal royal titles of 'prince' or 'princess' that they were entitled to as direct grandchildren to the monarch, Queen Elizabeth, in the male line.

Instead, the couple had Louise and her brother styled as the children of an earl, taking on the titles of 'lady' and 'viscount' instead – though both may still be referred to as Royal Highnesses if they choose to take up those tiles later in life.

Currently twelfth in line to the throne, Louise won’t be taking on the mantle of Queen any time soon, but she's every bit as royal as her cousins who bear the titles of 'prince' or 'princess'.

Other notable royals were in attendance for the Easter Mass too, including Princess Beatrice, Prince William and Kate Middleton, and a solo Prince Harry, Meghan Markle likely staying at home as she's in the very final stages of her pregnancy.