Meghan Markle and Prince Harry’s daughter isn't a princess, but she could become one when Prince Charles takes the throne

• Meghan and Harry's daughter Lili could receive a princess title when her grandfather is king.
• The monarch's grandchildren in the male line are eligible to receive titles.
• It will ultimately be Prince Charles' decision.

The Duke and Duchess of Sussex's newborn daughter, Lilibet "Lili" Diana Mountbatten-Windsor, was born without a royal title.

But that's not to say she won't be granted one when her grandfather, Prince Charles, becomes king.

The Letters Patent 1917, an ancient decree written by Queen Elizabeth II's grandfather, George V, states that only the children and great-grandchildren on the direct male line of the monarch will gain official royal titles.

An exception was made for Prince William's children when Prince George was born in 2013. The Queen issued her own Letters Patent, which ensured that all of William's future children would receive HRH status and royal titles.

This exception was not issued to Prince Harry and Meghan Markle's children.

Therefore, while Queen Elizabeth II reigns, Harry and Markle's children are not entitled to titles or HRH status. When Charles takes the throne, however, 2-year-old Archie could become a prince, and Lili could become a princess.

Charles may decide against issuing his grandchildren titles as part of his plan to 'slim down' the monarchy

Royal historian Marlene Koenig told Insider Charles could issue his own Letters Patent which would prevent Archie and Lili from gaining royal titles.

This is partly because the current Letters Patent is out of date, as it only references children in the male line. But it could also be due to Charles' reported plan to "slim down the monarchy."

Charles reportedly plans to reduce the number of senior working royals to a small group of eight. This would mean reducing who in the family is funded by the sovereign grant, the public funds used to support the royals, The Times reports.

The royal family could face an estimated $44.5 million shortfall due to the impact of the pandemic, Forbes reported in September 2020. However, the royals have "no intention of asking for extra funding," the Queen's financial officer Sir Michael Stevens said in a statement at the time.

Koenig, an expert on British and European royalty, said those who are eligible to receive titles in the future could be restricted to "the children of the Sovereign, the children of the heir apparent, and the children of the eldest child of the heir apparent."

She added that even if Archie and Lili aren't given the official titles, they will still technically be a prince and princess of the United Kingdom when Charles becomes the monarch.

She said this is apparent when looking at "the precedent set" by Prince Edward and his wife, Sophie, Countess of Wessex. Their children, Lady Louise Windsor and James, Viscount Severn, are the grandchildren of the Queen and do not have prince and princess titles.

"Sophie said recently that she knew her children were royal. But the Queen decided, and they agreed their children would have the style of children of an Earl. Even though they are technically prince and princess," Koenig added.

Buckingham Palace and Clarence House did not immediately respond to Insider's request for comment.