Palace marks Prince George and Princess Charlotte's first day of school with new photo

Summer is officially over for the Cambridge children, who kicked off the new school year on Sept. 5.

Prince George and Princess Charlotte were spotted arriving at Thomas's Battersea on Thursday morning, alongside the Duke and Duchess of Cambridge who accompanied their children for the big day.

While Prince George has been a student Thomas's Battersea since 2017, it was Princess Charlotte's first year at the South London Prep school.

And to mark the milestone, the royal family has released an official portrait of the two, which was captured by the Duchess of Cambridge on the steps of Kensington Palace. The snapshot shows George and Charlotte, both in their official uniforms, hugging and smiling for the camera.

While the Duchess of Cambridge was unable to attend Prince George's first day of school due to morning sickness while pregnant with Prince Louis, she was there to support Charlotte, introduce her to the lower school's headteacher Helen Haslem and escort her to her classroom.

Although the four-year-old princess was seemingly nervous and hid behind mom Kate for the first few moments, she's also excited for the new adventure with her big brother. “First day! Very excited,” Prince William told the headteacher while walking in with his kids.

See more of Charlotte's big day in the video above.