The Duke of Cambridge was given an avocado from a child to help cure Duchess Catherine's morning sickness.

The 35-year-old royal recently took a trip to Liverpool, and during his stay he visited a leisure centre in Wallasey in Merseyside where he met with a four-year-old boy named Archie Weatherall.

And during Prince William's encounter with the youngster he was given the green fruit wrapped in a big bow to pass on to his 35-year-old spouse, who is expecting their third child, because the child thought the food item would help the brunette beauty overcome her illness.

When William received the generous offer he promised Archie he would give the item to his partner and wished his mother well.

The Headteacher at Riverside Primary School, Christina Lahive, told the Express Online: "He [William] said he'd take it to her and see what happens - and said good luck for Archie's mummy."

William - who also has four-year-old son Prince George and two-year-old daughter Princess Charlotte with Catherine - also received cuddly toys from fans during his visit, but Archie's gift marked the first time the star has ever received an avocado from a fan.

Christina added: "He [William] said he's never been given an avocado before."

Duchess Catherine announced in a statement she was expanding her brood, but was battling hyperemesis gravidarum, which she endured during her first two pregnancies, and was resting at her home.

The statement read: "Their Royal Highnesses The Duke and Duchess of Cambridge are very pleased to announce that The Duchess of Cambridge is expecting their third child. The Queen and members of both families are delighted with the news.

"As with her previous two pregnancies, The Duchess is suffering from Hyperemesis Gravidarum. Her Royal Highness will no longer carry out her planned engagement at the Hornsey Road Children's Centre in London today.

"The Duchess is being cared for at Kensington Palace."