The princess, just shy of her third birthday, is the first female in the royal family to keep her spot for the throne following the birth of a younger brother.
WATCH: Kate Middleton and Prince William leave St. Mary’s Hospital on Monday with their newborn son to cheers and applause.
The 2013 Succession to the Crown Act updated the rules so that girls wouldn’t have to fall back in the succession to make room for a male sibling. The change means that all children born after 2011 keep their spot according to age.
“In determining the succession to the Crown, the gender of a person born after 28 October 2011 does not give that person, or that person’s descendants, precedence over any other person (whenever born),” the act reads.
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The law, passed just before Prince George was born, sought to modernize the way succession works in the royal family.
Here’s the current lineup for the throne: Queen Elizabeth II, then Prince Charles, then Prince William, then his children in order of age — Prince George, who is four years old, Princess Charlotte, who turns three on May 2, and then the newborn, whose name has not been revealed.
While Charlotte’s spot stays the same, her uncle, Prince Harry, dropped one spot this morning and is now sixth in line for the throne.
The updated succession rules also replaced the Royal Marriages Act 1772, meaning that only the first six in line for the throne now need the Queen’s permission to marry.
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Details on the newest royal
Kensington Palace confirmed Monday that the Duchess gave birth to a baby boy weighing eight pounds, seven ounces.
He was delivered at St. Mary’s Hospital in London, where his siblings Prince George and Princess Charlotte were delivered in 2013 and 2015, respectively. Both William and Prince Harry were also born there.
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The child was born at 11:01 a.m. GMT (6:01 a.m. ET), a few hours after Middleton was admitted to the hospital in labour.
“The Queen, The Duke of Edinburgh, the Prince of Wales, the Duchess of Cornwall, Prince Harry and members of both families have been informed and are delighted with the news,” the palace said.
WATCH: More coverage of Princess Charlotte and Prince George
It’ll likely be a few days before his parents reveal the baby’s name.
— With files from Global News reporter Chris Jancelewicz
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