William and art history student Kate Middleton, both 22, will travel to the late Queen Mother's secluded and sprawling Birkhall estate, where William owns a four-bedroom cottage, The Mirror reported Monday.
His father, Prince Charles and Camilla Parker-Bowles will be staying a 10-minute walk away.
Royal author Ingrid Seward said the announcement appears to indicate the royal family has accepted Middleton as William's official girlfriend.
"This romance is now more serious than most people realize," she said, adding "I am sure Camilla will be charming to Kate."
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