Photos: Royal Family/Twitter

The little royal looked slightly nervous as he headed to his first day of classes on September 7.

Four-year-old Prince George arrived at Thomas's Battersea school in south London earlier today, walking hand-in-hand with his dad, Prince William.

The pint-size royal looked slightly nervous as he greeted Helen Haslem, a senior teacher who later introduced him to the other students.

He will be known among teachers and students as George Cambridge, say Kensington officials. Twenty-two other children will be in George's class this year.

Catherine, the Duchess of Cambridge, who recently announced her third pregnancy via a Kensington Palace press release, missed her son's big day due to acute morning sickness, a result of the condition hyperemesis gravidarum.

"Unfortunately the Duchess of Cambridge remains unwell," a Kensington Palace statement said this morning.

Prince George arrived for his first day of school strapped into the back of the family Range Rover. Sources say he's excited to report back to Mum about his first classes. "She would have done anything to be here," a source said of the Duchess. "It's a big day in her son's life but she really has been very sick."

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