Kate Middleton

This is why Kate Middleton wore red to introduce the new prince

Or, at least, it's why we think she did...
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2. A tribute to St. George's Day

Not only did royal baby number three arrive yesterday, but it was also St. George's Day.

Traditionally an occasion where people wear a red rose on their shirts to honour the patron saint of England and protector of the royal family, it is possible Kate was feeling so patriotic that she insisted she wear the hue all-over.

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3. She liked the dress

We know. Outrageous suggestion. But, against all odds, perhaps Kate wore the dress because she liked the way it looked and felt on her just-gave-birth-11-hours-ago body...

While you ponder the options, scroll down and take a look at all of Kate Middleton's style hits since she became the Duchess of Cambridge: