The Duchess of Cambridge will present the BBC's Sports Personality of the Year award and the lifetime achievement honour tonight, St. James's Palace said.
Catherine has not been seen in public since leaving the King Edward VII's Hospital in London on December 6.
She received three days of treatment for a condition known as hyperemesis gravidarum, which leaves expectant mothers so ill they cannot keep food or liquids down.
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The formal Brexit process may have begun today - but experts say it may take up to six years to strike a new trade deal with the EU.
International trade lawyer Miriam Gonzalez Durantez says Brexit negotiators need a "360 degree view" to secure a "constructive" deal.
The former footballer said he hopes speaking about his grief will help others who find it difficult to talk about their feelings.