The Prince pulled out of the memorial for his godfather King Constantine following the news.

How Prince William 'found out' about Kate’s cancer diagnosis before pulling out of Windsor Castle memorial service

Downing Street has urged the public to 'get behind the Princess of Wales'.

Leave Kate alone: Downing Street urges public to 'get behind Princess' as she recovers from abdominal surgery

Kate and William were pictured visiting the farm

Shopper who filmed Kate and William in farm shop urges 'delusional' conspiracy theorists to 'lay off' princess

Tina Brown, former Vanity Fair editor, joined LBC's Andrew Marr this evening

Princess Kate conspiracies ‘should worry Buckingham Palace’ as royals need ‘massive reboot’, expert warns

Prince William (L, R) on a visit to Sheffield today

Prince William breaks silence with touching remark wishing Princess Kate was 'by his side'

Heidi Agan confirms it is not her in a recent video of William and Kate leaving a farm shop in Windsor

'I was 120 miles away!' Kate lookalike confirms it's not her in farm shop vid and shuts down 'crazy' conspiracies

Prince William was cheered by crowds in Sheffield

Prince William cheered by crowds as he's seen for first time after trip to the farm shop with Princess of Wales

High-level royal aides are planning Kate's return to royal duties after she was spotted at Windsor Farm Shop

Operation Comeback Kate: Inside secret back-to-work plan for Princess's return to public life

Kate and William were pictured visiting a farm shop in Windsor together

'Remarkable' Princess of Wales deserves privacy as she recovers, minister says as video emerges of farm shop trip

Kate and William were pictured visiting the farm

Smiling Kate spotted on shopping trip with William as she continues recovery from surgery

The Princess of Wales was said to be "happy, relaxed and healthy” on a visit to a farm shop in Windsor

Princess of Wales ‘happy and healthy’ on visit to farm shop with William in first public sighting since surgery

The King is determined to attend his official birthday celebrations - even if he has to enjoy Trooping The Colour from a carriage.

King Charles ‘determined’ to attend Trooping the Colour but could watch ceremony from podium and not on horseback

Prince William has paid tribute to his mother who taught him that as he attended the Diana Legacy Award - while Prince Harry was set to appear via video link after his brother left the event

Prince of Wales marks 25th anniversary of Diana Legacy Awards - with Harry joining via video link after William left

The Prince of Wales' comments about his wife come as the couple are facing intense scrutiny about an edited family image released to mark Mother's Day.

'My wife is the arty one': William sings Kate's praises as he brushes off Mother's Day photo row on visit

Prince William plays basketball on visit to youth centre

Prince William puts Kate picture row behind him as he plays basketball on visit to youth charity

Prince William and Harry will both make appearances at the memorial event.

Still contintents apart - Harry and William to attend Diana memorial event but will not appear at the same time

Kate's Mother's Day family photo (L) sparked controversy. Harry and Meghan (R)

Princess of Wales is 'recovering well and will be back by Easter' despite photo editing storm, royal insiders claim

Kate edited controversial Mother's Day picture (l) to make it 'as good as possible' William and Camilla at the Commonwealth Service

Royals ‘rally around Kate’ as ‘Photogate’ played down by insiders as ‘bump in the road, not an earthquake’