Six-year-old Daithi Mac Gabhann has been awarded the freedom of Belfast City following his family's campaign for changes to organ donation laws.
The Organ and Tissue Donation (Deemed Consent) legislation, also called Daithi's Law after the Belfast boy, changes the way consent for donation is granted and came into effect on Thursday.
Most adults in Northern Ireland are now considered potential organ donors.
The intent of the new legislation is to increase the current number of organs available to people in need of a transplant.
Adults are now deemed to have given consent as a potential organ donor after their death unless they choose to opt-out or are in an excluded group.
Daithi has been on the waiting list for a heart transplant since 2018, and his family have campaigned for a move towards soft opt-out law and to promote organ donation.
Belfast City Council said the decision to bestow the city's highest honour on the six-year-old is in recognition of his campaign.
The Lord Mayor and Belfast City Council conferred the Freedom of the City onto Daithi at an event at Belfast City Hall on Saturday evening.
A circus-style big top tent was erected on the front lawns of City Hall to welcome Daithi's friends and family for the event.
The Lord Mayor of Belfast Councillor Tina Black was delighted to lead the celebratory event and said: "Daithi is an exceptional and special little boy who has inspired and given hope to other young people waiting for a donor."
Daithi was born with hypoplastic left heart syndrome, meaning the left side of his heart did not form correctly.
Lord Mayor Tina Black said she was delighted to lead the celebratory event.
She said: "Daithi is an exceptional and special little boy who has inspired and given hope to other young people waiting for a donor.
"Daithi is an inspiration being so brave, at such a young age, in undergoing several open-heart surgeries in recent years.
"It is fantastic that he is now being recognised for his tireless campaigning in raising awareness around organ donation, and his success at bringing about a change in legislation.
"The Freedom of the City on Daithi showcases the immense pride we as a city have for him and I am both humbled and delighted to be here today to congratulate and celebrate with courageous Daithi and his family."
Daithi's father Mairtin Mac Gabhann said: "Today is Daithi's day - it is testament to his remarkable character and tremendous spirit.
"We are so delighted to have the support of this amazing city on this historic day. We are forever grateful."
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