The Duke and Duchess of Rutland’s eldest daughter won’t be the only blue-blooded woman sidelined by the archaic rule of male primogeniture.

The Duke of Northumberland’s title will similarly bypass his 40-year-old daughter, Lady Katie, in favor of her younger brother, George Percy, Earl Percy, 38.

This age-old tradition of male succession has sparked a European-wide campaign known as Daughters’ Rights, pushing for gender equality in aristocratic inheritance.

Among the campaign’s prominent supporters is Catherine FitzGerald, the wife of actor Dominic West, who stands to inherit her father Desmond’s title, Knight of Glin.

The movement is gaining traction, attracting both aristocrats and political figures.

Former Prime Minister David Cameron once declared that the idea of a younger son outranking an elder daughter for the throne is no longer acceptable.

Boris Johnson, another former Prime Minister, reportedly initiated a review of male primogeniture to promote gender equality in Parliament.

However, not everyone is ready to abandon tradition. Earl Spencer, 58, insists on passing his title to his son Louis, bypassing his eldest daughter, Kitty.

“If I chose Kitty, it would be against all the tradition that goes with Althorp,” he remarked in 2015, defending the principle of primogeniture.

“I get the problems with it as a concept. But it has kept the estate intact.”

Earl Spencer’s stance is also practical. He has seven children from three marriages, and dividing the estate could become complex.

Despite this, Louis shares a close bond with his sisters, evidenced when he walked Kitty down the aisle at her wedding.

The Spencer siblings enjoyed a privileged yet private upbringing in Cape Town, where their parents moved in 1995 to shield them from public scrutiny.

Their parents divorced in December 1997, shortly after Princess Diana’s tragic death, and Charles Spencer returned to the UK.

Louis remained largely out of the spotlight during his youth, with few public appearances.

His first high-profile outing was at Prince William and Kate Middleton’s wedding in April 2011, though he was overshadowed by his glamorous older sisters.

Four years later, Louis made a surprising appearance on Nicki Minaj’s Instagram, arm-in-arm with the rapper, who joked about their “wedding photo.”

Louis truly stepped into the limelight at Prince Harry and Meghan Markle’s wedding in 2018, attending with his mother and sisters.

Looking dapper in a morning suit, he became an unexpected star of the day, earning numerous playful marriage proposals online.

His resemblance to Prince Harry led to the nickname “Harry Lite,” and Tatler named him one of the world’s most eligible bachelors.

Louis’s family connections and good looks might benefit him as he pursues his acting dreams.

In 2019, Earl Spencer shared that Louis was living in London, attending drama school, and working hard to achieve his acting ambitions.