Prince William stands in for Kate at Maltese 50th anniversary of independence

Duchess of Cambridge is still suffering from severe morning sickness

Prince William will stand in for the Duchess of Cambridge, who is expecting her second child is suffering from severe morning sickness (WILLIAM WEST/AFP/Getty Images)

Prince William is filling in for the Duchess of Cambridge after severe morning sickness forced her to cancel her first solo overseas visit to Malta at the last-minute.

The Duchess, who is pregnant with her second child, was due to celebrate with the Maltese people the 50 anniversary of their independence from the United Kingdom on 21 September 1964.

She had been in doubt after suffering from hyperemesis gravidarum for around two weeks, but made the decision on Wednesday not to attend after consultation with her doctors.

After announcing her pregnancy last Monday, the Duchess has been forced to cancel a number of engagements – missing the opening ceremony of the Invictus Games, a brainchild of her brother-in-law Prince Harry – as a result of feeling unwell.

Hyperemesis gravidarum, which affects 3.5 per 1,000 pregnancies, causes severe vomiting and can lead to dehydration, weight loss and a build-up of toxins in the blood or urine, called ketosis.

Last week Prince William said the couple had experienced a “tricky few days” during which the Duchess was treated at home by medical staff.

The Duke will follow the same itinerary as prepared for the Duchess, formally meeting Malta’s President Marie-Louise Coleiro Preca and Prime Minister Joseph Muscat.

He will also watch a historical re-enactment in the capital Valleta and be shown historical documents in the national library.

Additional reporting from PA