Kate, who is more than eight months pregnant, will stay at home, but William and Harry are expected to be among the congregation to watch Thomas van Straubenzee marry Lady Melissa Percy.
The Duchess' final official public appearance was last weekend when she attended the Trooping the Colour ceremony with other members of the Royal Family.
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Primary school teacher Lewis Siddall was killed in an 'unprovoked and senseless' act of violence, family and police say.
Make the most of the mild air.
The vehicle is captured on CCTV crashing through the shop window and hitting a browsing customer who was lucky not to be seriously hurt.