Daniel O'Donnell has warned that people across Ireland need to continue the fight against cancer because nobody knows when it will strike.
The world-famous singer was speaking as he sent a message of hope to those taking part in Donegal's Relay for Life event.
The event, which takes place at the Atlantic University Campus in Letterkenny is a 24-hour journey of hope for those affected by the disease.
Hundreds of people have gathered to walk in celebration of cancer survivors and in memory of those who are no longer with us.
The event, the 11th such gathering, also raises vital funding for cancer research and local services.
Patron Daniel O'Donnell facetimed into the event from a cruise to Alaska to send his best wishes. "I hope it's a great success. Carers and survivors alike, I wish you all the very best."
"This is an important gathering for so many people and such an important gathering to raise as much money so that many people in the future will gather like you."
And he added poignantly "We just do not know who will get a cancer diagnosis today, tomorrow or sometime in the future."
Daniel is one of those hit directly by cancer after wife Majella was diagnosed with breast cancer in 2013.
Majella has gone on to fight the disease raising more than €500,000 with a live headshave on RTE's Late Late Show and is now the Global Hero for Hope for Relay for Life.
As well as non-stop walking, the event features choirs singing and other events.
One of the most emotional aspects was the Luminaria Candle of Hope Ceremony which saw 5,000 candles light up the night last night.
Also central to the ceremony is the Survivors Choir, with a brand new song being performed for the first time on Saturday.
The choir will be led by Donal Kavanagh, Highland Radio broadcaster and cancer survivor, with Moya Brennan and family providing the music.
