Here's how Princess Charlotte reportedly spent her third birthday with new baby brother

Princess Charlotte spent her big day with the new Royal baby in the cutest way.

Charlotte was treated like a queen during the celebration of her third birthday at Kensington Palace on May 2, 2018.

Prince William and Kate Middleton shared official photos of the birthday girl with their third child.

The sweet snaps were posted by the Kensington Palace on Instagram.

One photo shows Prince Louis sleeping while Charlotte kissed him on the forehead. The other image shows the newborn lying on a bed while looking at something.

'The Duke and Duchess of Cambridge are very pleased to share two photographs of Princess Charlotte and Prince Louis, taken by The Duchess at Kensington Palace.‬ This image was taken on 2nd May, on Princess Charlotte’s third Birthday,' Kensington Palace captioned the photos.

The Palace added: '‪The Duke and Duchess would like to thank members of the public for their kind messages following the birth of Prince Louis, and for Princess Charlotte’s third birthday.‬'

As reported by US Weekly, the details of her birthday were kept private, but she celebrated with a cake. She also spent time with Prince Louis.

“Charlotte is really enjoying having a younger brother to play with,” a royal insider told US Weekly. “She’s taking her big sister duties very seriously. She won’t leave baby Louis’ side.”

The royal insider added that Charlotte has taken some pointers from Prince George. The four-year-old has proven to be very “protective” of his younger siblings.

“Charlotte is just like him," the insider said. "They have a great bond, and a similar connection is growing between Charlotte and Louis.”

The insider continued that Charlotte is "a girly girl” and "very confident.”

“She’s not afraid of a grazed knee and it’s not going to stop her from running around. She moves at the speed of light!” the insider explained.

The insider revealed that there's a possibility of seeing more royal babies in the future as William and Kate "never say never!"