Kate Middleton surprised children in a central London intensive care centre, just hours after attending the Queen's Service of Thanksgiving.
The Duchess of Cambridge spoke to parents, patients and staff at the Evelina Children's Hospital in Lambeth, south London, on Friday.
It's believed she wanted to boost morale among those who couldn't join the Queen's Platinum Jubilee celebrations, and reveal the work of medical workers in children's healthcare, as a royal patron of the hospital.
The children included seven-day-old Florence Clements, who has heart problems, wearing a tiny knitted crown above various tubes and electrodes attached to her face.
Others at the hospital pitched in to make colourful decorations honouring the jubilee.
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They included corgi-shaped bunting and a sparkling crown above a cut-out of the number 70 referencing the number of years since the Queen’s coronation.
The Evelina Hospital is part of Guys’ and St Thomas’ NHS Trust, which has had the Duchess’ royal patronage since 2018.
Hospital staff shared the news of Kate’s visit on Saturday along with pictures of the Duchess alongside Florence and her parents.
They wrote on Twitter : ‘We received a very special surprise last night! Our Patron, HRH The Duchess of Cambridge, dropped in for a private visit to meet our patients, families and staff unable to join in the celebrations this weekend.
‘Luckily the hospital was already decked with Platinum Jubilee decorations made by some of the children and young people we are caring for. Thank you YRH for thinking of us.’
Kate’s visit was focused on the hospital’s paediatric intensive care unit, although it provides a wide range of services from pre-natal care to supporting teenagers with complex conditions as they transition into adulthood.
The 40-year-old has frequently used her patronage to champion children’s healthcare across the Trust.
She is thought to have spent the following day baking with her children, George, Charlotte and Louis, before heading to Wales with the eldest two and William for a special Jubilee concert in Cardiff Castle.
The Cambridges shared pictures of Kate and her kids making cupcakes which were due to be shared with residents at a street party in the city on Sunday.