The two siblings were apparently taken by surprise when their family curtsied and bowed to the Queen’s coffin.
George and Charlotte were watching the procession, with the Queen’s coffin passing by.
But when Charlotte noticed the Countess of Wessex was curtsying, she immediately followed in her steps and curtsied as well.
George, for his part, bowed only after his sister curtsied.
Twitter users applauded the siblings for doing their best to comply with the royal protocol.
Lady Mandi said: “Charlotte and her little curtsy’s are the cutest thing I’ve ever seen.”
“Charlotte is observant smart little lady,” berniefan reacted with a heart emoji.
Rhoda Nielson said: “Love how Charlotte looks at Sophie and follows her lead.”
READ MORE: George and Charlotte look grown up entering service with Kate
After questions about their presence at the Queen’s funeral, George and Charlotte attended the royal event with their parents – Prince William and Princess Kate.
George, 9, and his younger sister Charlotte, 7, were the youngest royal mourners paying their respects to their great-grandmother on Monday.
The Queen’s great-grandson, who became second in line to the throne, was flanked by his father – King Charles III’s immediate heir – her mother Kate and sister during the procession that led them to Westminster Abbey.
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