The Duchess of Cambridge attends Paddington charity event

Video caption, The Duchess of Cambridge and Paddington danced on the station platform

The Duchess of Cambridge has made a surprise visit to a charity event at Paddington station in west London.

Princes William and Harry had already planned to attend but Catherine also joined them on Monday.

It is her second public appearance since it was announced she was expecting her third child.

The duchess, who has been suffering from severe morning sickness, met children and the stars of the film Paddington 2.

Kensington Palace said Catherine is "better, but she's still suffering".

Wearing an outfit by designer Orla Kiely, she greeted children who had been selected by the Duke, Duchess and Prince's Charities Forum.

There are more than 30 organisations involved in the forum which the royals are patrons of.

Image source, PA

Image caption, It is the second time the duchess has been seen in public since the announcement

Earlier this month, Catherine was spotted for the first time since the baby news at a mental health event at Buckingham Palace.

She is not thought to be resuming her full royal schedule.

The royals were forced to announce her pregnancy before her 12-week scan - when most women have their first scan - due to her sickness.

She was also unwell during her pregnancies with her other children Charlotte and George.

Image source, AFP/Getty Images

Image caption, The royals met the star of the films - Paddington Bear

Image source, PA

Image caption, Kensington Palace announced Catherine's third pregnancy in September

Image source, PA

Image caption, And actor Hugh Bonneville who plays Mr Brown