When her parents Prince Edward and Sophie Countess of Wessex married, The Queen revealed that their children will not be burdened with royal titles and as a result Louise was styled as a Lady.
This means Lady Louise has avoided much of spotlight that her cousins could not, however she is best known her adorable appearance as one of Duchess Catherine of Cambridge's bridesmaids at her 2011 wedding to Prince William.
She was then only eight years old, but has since grown into a very confident young lady.
Her Majesty attended The Royal Windsor Horse show at Windsor castle last week and the Queen was kept company by three generations of her family.
Among them was her granddaughter, 11-year-old Lady Louise Windsor, her daughter-in-law Sophie Countess of Wessex, son Prince Edward and her grandson James Viscount Severn.
Queen Elizabeth was spotted laughing as she watched the horse show, and seemed delighted to be spending time with her family.The Horse show which is in its 72nd year is a five day-long event and The Queen has not missed a single one since its birth back in 1943.
Lady Louise Windsor shares her Grandmother's love of equestrian sport and was seen entertaining her younger cousins and the Queen's great-grandchildren, Savannah and Isla Phillips during the event.
It's fabulous to see the new generation of Royals growing into their roles!