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Kate Middleton may be pregnant with the heir to England's royal throne but that is not keeping the Duchess of Cambridge from heading to the races, literally.

The 31-year-old and her husband, Prince William, made a surprise appearance today at Cheltenham Gold Cup Day, the final day of the annual horse racing event in Gloucestershire.

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The duchess was spotted in the same maternity chic look she has maintained throughout her pregnancy, donning a short camel-peach colored coat over her baby bump, accented by brown suede boots and a brown clutch. On her head she wore a Betty Boop pillbox hat by designer James Lock, reported by British media to be the same hat she wore to a friends' wedding with William last month.

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Middleton and William, 30, arrived to the festival just before lunch and spent with time William's cousin, Zara Phillips, an Olympic equestrian rider, and her husband, Mike Tindall, the part-owner of a horses competing in the race, according to People magazine.

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The high-profile public outing, Middleton's sister, Pippa, was spotted at the festival yesterday, was another marker for the pregnant Duchess as she continues to raise her profile after a bumpy start to her pregnancy.

Middleton was hospitalized in December, early in her pregnancy, after falling victim to severe morning sickness.

After a vacation on the exclusive Caribbean island of Mustique with William and her family, Middleton stepped out last month to meet with women recovering from addiction and made headlines earlier this month when she may have inadvertently reveal the gender of her unborn child while at a public event in Grimsby.

Middleton is due to give birth in July.