Prince Harry said the winners of 2013 WellChild Awards, which recognises courageous youngsters, were "unbelievably brave" and left him "hugely humbled."
He said: "I'm hugely humbled to be patron of WellChild and I count myself incredibly lucky to be patron, as well as coming down here this evening.
"It's always so clear for everyone to see how brave and inspirational the children are, but very easy to forget what a huge effect it has on the parents, nurses and all the family."
Prince Harry has met winners of 2013 WellChild Awards, which recognises courageous youngsters, at the Dorchester Hotel in London.
The Prince is a royal patron of the charity and called the award winners "unbelievably brave."
Prince Harry saw his baby nephew smile for the first time today and said that being an uncle is "fantastic."
Speaking to children at the 2013 WellChild Awards for courageous youngsters, the royal said: "I've just literally seen him. It was the first time I've seen him smile."
Nikki Christou, who suffers from an incurable malformation in her face which affects her nose, cheekbone and right eye, was keen to talk to Harry about Prince George because of a series of coincidences.
The nine-year-old shares his July 22 birthday, has a father called George and a brother called Alexander - the baby Prince's middle name.
Harry told the youngster the coincidences were "very, very weird" and Nikki said the Prince was "really nice."
Prince Harry gave a six-year-old boy, who is bravely battling a life threatening illness, a round of applause after the boy sung a song for him about digging his garden.
Jonathan He, who won the award for Most Inspirational Child for boys aged three-to-six year olds, said the royal praised him for the song, and added: "He said it was brilliant."
Prince Harry and a host of celebrities have arrived at the 2013 WellChild Awards, which celebrates the courage of children who are coping with serious illnesses.
A six-year-old boy, who will be presented with an award by Prince Harry for bravely battling a life threatening illness, has told ITV News he wants to be a chef in the future after being unable to eat for five months.
Jonathan He will be presented with the Inspirational Child prize at the 2013 WellChild Awards by the royal tonight.
The six-year-old told ITV News Correspondent Nina Nannar that he plans on entering junior MasterChef and added: "I could be a champion".
Jonathan also recited a poem he wrote on his favourite food - sausages.
Prince Harry will present an inspirational child award to a six-year-old boy who is bravely battling a life threatening illness.
Jonathan He suffers from a rare genetic condition called x-linked CGD, which has led to severe infections, long-term therapy and a high-risk blood transplant, and congenital glaucoma - meaning he is partially sighted.
The six-year-old was picked out of hundreds of nominees to win the Inspirational Child prize in the 2013 WellChild Awards.
Jonathan told ITV News Correspondent Nina Nannar he planned on telling WellChild patron Prince Harry two jokes when he meets the royal this evening.