Kate Middleton Makes the Day of Young Fan

Duchess of Cambridge Kate Middleton may be just a duchess, according to royal titles, but she's a queen in the mind of one loyal subject, thanks to a simple act of kindness.

Middleton, 31, drew thousands of fans to her March 5 appearance in the town of Grimsby, but lost among them was one of her biggest supporters, 10-year-old Isabella Clarkson.

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Isabella and her siblings, 8-year-old sister, Alice, and 4-year-old brother, Reuben, traveled with their school to try to meet the duchess but because of bad weather and huge crowds only got a brief glimpse of her car and her waving hand, the Grimsby Telegraph first reported.

Upset by her family's missed opportunity to see a real-life royal, Isabella took her disappointment to paper and wrote a letter to Middleton, who's pregnant with her and Prince William's first child.

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"I'd spent ages making a glittery banner to hold the night before, but I don't think she saw it," Isabella told the paper. "I wrote a letter to her afterwards saying how disappointed we all were not to get to meet her."

What happened next transformed Isabella and her family into mini-celebrities in their town.

"Then we got a reply," Isabella said. "My mum was so excited when it arrived at our house that she brought it into school and the teacher read it out to the class." The letter, addressed to Isabella and signed by Claudia Spens, identified online as the head of general correspondence for the Office of TRH, thanked the youngster for her "lovely letter."

"The Duchess of Cambridge was immensely touched that you should take the trouble to write as you did. It really was most thoughtful of you and Her Royal Highness has asked me to send you her warmest thanks and best wishes," read the letter, a copy of which the family provided to the Grimsby Telegraph.

Isabella, who says she plans to frame the later, in reply paid the duchess a high compliment, comparing her to her late mother-in-law, Diana, Princess of Wales.

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"I think Kate is doing all the good work that Princess Diana did and she seems very generous," she told the Grimsby Telegraph.

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