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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She told reporters: "I don't think it's fully sunk in how really bad that could have been, I know it's not the right decision."
Jonathan Theobald said: "The weather can change quickly and a car can become lethal, I've discovered that the hard way."
Political parties across the country suspended their General Election campaigns following the Manchester Arena terror attack on Monday.