Secret royal baby talk? While Prince William awaits the birth of his first child with Kate Middleton, a source exclusively tells Us Weekly that the royal had one last meeting with his grandmother, Queen Elizabeth II, on July 4.

An insider tells Us that William, 31, packed a large bag and freshly pressed suit before leaving Kensington Palace (where he is staying with his pregnant wife) to head to Sandringham Castle in Norfolk, England. There, the source tells Us the dad-to-be had "private meeting" with Queen Elizabeth, 87.

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Perhaps the two were having last-minute discussions over baby names? Shortly after, on July 8, a rep for Kensington Palace announced the royal baby-to-be has been given an official title. "The royal couple's child will officially be known as His or Her Royal Highness Prince or Princess of Cambridge," the rep confirmed. (Earlier this year, Queen Elizabeth II changed a century-old decree that daughters would be referred to as "ladies" rather than "princesses," stating that all children of the eldest son of the Prince of Wales would receive the titular dignity of Prince or Princess.) Regardless, the royal baby -- be it a he or she -- will be the third in line to the British throne, and will one day rule as king or queen.

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William and Kate's little prince or princess' actual name, however, may not be released until well after the birth. "The couple have yet to decide on a name and probably won't until the day of the birth," a palace aide told Us. Indeed, William's parents Prince Charles and the late Princess Diana took seven days to decide on his name.

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Although the royal baby is due any day, William still plans to play in the Jerudong Trophy Match, an annual charity event, at Cirencester Polo Club in Gloucestershire on Sunday, July 14. A Palace aide confirms to Us that William will attend "if he can. We shall see on the day. William wants to support the event for his charities, but he will only go if it's possible."

This article originally appeared on Prince William Had "Private Meeting" With Queen Elizabeth II Ahead of Baby's Birth