Daniel O'Donnell and Majella both attended the 25th annual Light Up a Life Campaign which was helad at Our Lady's Hospice in Harold's Cross earlier today.
Up to 15,000 people this year's fundraising event, which heralds the start of Christmas at the hospice.
Daniel O'Donnell said: "We are all aware of the great work that is being done here."
Majella O'Donnell told RTÉ news that both her grandmother and aunt had passed away at the Dublin-based hospice.
She said: "They were just fantastic and that's many years ago and they are still doing a fantastic job."