The much-loved Britain’s Got Talent star has been holidaying in Donegal for the past couple of days.
It is believed Ms Boyle has been sight-seeing around Inishowen and spent time in Carndonagh on Saturday.
One mass-goer at St Mary’s Oratory in Buncrana revealed how the singer had chatted with her young grand-daughter.
“She was really lovely. She shook hands with my grand-daughter at mass and said some lovely things about her. A lovely woman,” said the mass-goer.
She was also spotted having lunch in the Half-way House in Burnfoot where she even indulged in a glass of Guinness before chatting with customers.
Word of Susan’s surprise appearance soon spread and the bar was packed within minutes!
Ms Boyle, who became an over-night superstar after appearing on the hit television talent show, spent many summers in Donegal.
Her parents are originally from the county and she has revealed in the past how she often spent many happy times here.