Royals British Royal Family Why Princess Charlotte Just Made History With the Arrival of Her New Baby Brother Princess Charlotte's position for the crown wasn't affected even though her mom, Kate Middleton, gave birth to a boy By Dave Quinn Dave Quinn Dave Quinn is a Senior Editor for PEOPLE. He has been working at the brand since 2016, and is the author of the No. 1 New York Times best-selling book, Not All Diamonds and Rosé: The Inside Story of the Real Housewives from the People Who Lived It. People Editorial Guidelines and Diana Pearl Diana Pearl Diana Pearl is a former writer and reporter at PEOPLE. She left PEOPLE in 2018. People Editorial Guidelines Published on April 23, 2018 08:40AM EDT Princess Charlotte has a new little brother — but her position in the line of succession won’t be affected by the arrival of the family’s newest addition. For the first time in history, a female royal’s spot in line to the throne won’t be bumped by the arrival of a younger brother. Thanks to the Succession to the Crown Act 2013, birth order determines who will become the next king or queen of the U.K., regardless of gender. Had it not been in place, Charlotte, who turns 3 on May 2, would have lost her spot if mom Kate Middleton had given birth to a boy. The legislation was first passed while Princess Kate was pregnant with Charlotte’s brother Prince George, now 4. It affects all royals born after Oct. 28, 2011, and also removed the disqualification placed on those arising from marriage to a Roman Catholic. Until 2013, older sisters would be moved down a spot in the order of succession if their parents had a younger son — like with Princess Anne after the birth of Prince Andrew and Prince Edward. Watch the full episode of Raising a Royal streaming now on PeopleTV.com, or download the PeopleTV app on your favorite device. Chris Jackson/Getty Images/PA Wire The New Royal Baby Is Almost Here! Here’s Exactly How the News Will Be Announced Currently, Prince Charles is the heir to the throne after his mother, Queen Elizabeth II. Prince William is second, with his kids Prince George and Prince Charlotte in the third and fourth positions, respectively. The new baby boy is fifth in line to the throne. With his arrival, Prince Harry is now sixth in line, and Prince Andrew, Princess Beatrice and Princess Eugenie will all move down a place in the line of succession with the arrival of William and Kate’s younger son. The royal couple announced they were expecting baby No. 3 in September 2017, and Princess Kate was admitted to the hospital on Monday, April 23, in the early stages of labor. RELATED VIDEO: Princess Charlotte Will Make History When Her New Royal Sibling Arrives Meanwhile, having wrapped the final official engagement of her third pregnancy last month, Kate has been getting ready for a whole new chapter. Though she stepped out with William for Easter service, the 36-year-old mostly nested over the past few weeks in Apartment 1A of Kensington Palace and helped her children adjust to the idea of a baby brother or sister. Both kids are “excited” for the impending addition, a friend told PEOPLE while noting, “Charlotte, as the youngest, may find it hard.” Kate “feels it’s an incredible privilege to be a mum,” added Peter Fonagy, head of the Anna Freud National Centre for Children and Families.