Fans supported Billie Eilish through her Electric Picnic show after she complained of feeling "really, really sick" before her performance.
The American singer, 21, headlined the first day of the festival at Stradbally Estate, Co Laois on Friday.
Social media videos showed her delivering her Barbie soundtrack hit What Was I Made For? in a white Nike shirt and baseball cap.
She was joined by the crowd who sang along to songs including Happier Than Ever.
Eilish had previously told her followers to help her at the concert.
In an Instagram story, she wrote: "I am really, really sick, and honestly really suffering.
"You know me and you know that I wouldn't cancel a show even if I was like literally dying... (this does feel pretty close tho lol) but the show must go on.
"I will see you tonight! But please keep in mind that I am trying my best and I'm gonna need your help tonight. Go hard for me."
Fans and critics alike hailed Eilish's headline set.
Source: Press Association
