The meeting comes as Harry prepares to join his brother, the Duke of Cambridge, at the statue unveiling in honour of their mother.
On Wednesday, Harry attended the ceremony put on by WellChild, a non-profit which supports seriously ill children and young people in the UK.
He referenced the recent birth of his second daughter, Lili, saying, “as a father of two, I feel all the more connected, inspired and in awe of the resilience of these families”.
The duke, who is back in the UK for the first time since the Duke of Edinburgh’s funeral, visited Kew Gardens in west London on Wednesday to meet the seriously ill children and young people at the private garden party and afternoon tea.
He was joined at the award ceremony by celebrities including Ed Sheeran, Ronnie Wood, Amanda Holden, AJ Pritchard and Abbie Quinnen, as well as singer Anne-Marie who performed an acoustic set.
The duke chatted about fatherhood with Sheeran, whose daughter Lyra was born last year, Hello! magazine revealed.
Sheeran said: “Congratulations, a girl right? We just had a little girl 10 months ago now. You’re still in the trenches now. How do you manage with two?”
“Two is definitely a juggle,” Harry said.
Speaking to another guest, Hello! revealed Harry said of Lili: “We’ve been lucky so far, she’s very chilled and seems happy to just sit there while Archie is running around like crazy.”
Asked about the statue unveiling, Harry said he “was just so glad” it could take place on Diana’s birthday, saying he had not been sure they would be able to.
The duke, dressed casually in a light blue jumper and dark trousers, met each winner in turn to present them with their awards, and spoke to them about how the last 18 months has been for them and their families during the pandemic.
Dozens of people attended the secluded event and a marquee was erected in the gardens next to Kew Palace where balloons of the charity‘s colours, purple and orange, decorated the tent
Large outdoor versions of famous board games were available for the children to play with, including Connect 4 and Lego.
Harry was seen chatting animatedly to guests and appearing relaxed.
In a statement released by WellChild, Harry said: “Since becoming patron of WellChild in 2007, this organisation and the people within it have held an extraordinarily special place in my heart.
“I wasn’t a father at the time, and yet the stories of these children and parents transcended that.
“I didn’t need to be a dad to feel the impact of this invaluable work.
“Now as a father of two, I feel all the more connected, inspired and in awe of the resilience of these families, who power through indescribable challenges with the support of WellChild.”
He added: “The health of our children, of all of us, could not have been more on the forefront of our minds during the past year.
“And, throughout this time, the WellChild community has set an example for how to show up and act with compassion for each other.
“I could not be prouder to be here, to meet this year’s WellChild Award winners, to thank the nurses and doctors for all they do, and to celebrate these amazing families.”
Harry returned from California alone for his trip to the UK and had been isolating at Frogmore Cottage in Windsor.
The area remained blocked off from the public throughout the day, with security guarding different entrances and exits into the space.
Among the winners was Carmela Chillery-Watson, who won the Inspirational Child 7-11 award.
Carmela, seven, has congenital muscular dystrophy, which weakens skeletal and respiratory muscles and causes heart defects.
During lockdown, she completed a series of challenges including a 2.6-mile marathon challenge in the garden, a London virtual WalkWithCarmela and a 30-day WonderWomanWalk, completing 300km with her mother, and raising more than £50,000 for Muscular Dystrophy UK.
Her mother Lucy said: “Carmela never complained once about her pains and discomforts. Just seeing the fundraising money increase was enough for her.”
WellChild is a cause that has long been important to the duke.
He retained his private patronage of the organisation despite his move to the US.
The duke was stripped of his royal patronages given to him by the Queen and his honorary military positions.
WellChild supports seriously ill children and young people in the UK to ensure they have the best chance to thrive – properly supported at home with their families.
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In December, the duke held a special video call with past winners of the WellChild awards, which recognise the achievements of children living with serious illnesses.
He described them as “unbelievably inspiring”.
Last year’s ceremony was cancelled because of the Covid outbreak.
Harry’s troubled relationship with William has been well documented, but the pair are set to gather together in the gardens of Kensington Palace on Thursday on what would have been Diana, Princess of Wales’s 60th birthday.
The brothers jointly commissioned the statue of their mother in 2017 – the 20th anniversary year of her death in a car crash – when their relationship was in a better place.
Harry, 36, quit as a senior working royal last year and has since raised a string of allegations about the royal family, the most damning being a claim of racism.
The royal brothers and Diana’s close family, thought to be her siblings, will attend the unveiling, along with the statue committee and others involved in the process of erecting it in the palace’s Sunken Garden.
Ian Rank-Broadley, who has a long track record of creating images of the royal family, was chosen to craft the statue, and he will be among the invited guests, along with Pip Morrison, who redesigned the Sunken Garden where the monument is located.