Ryan Tubridy was absent from his RTE Radio One show again this morning with concerns as to whether he will host Friday's Late Late Show.
The presenter has been off air since Wednesday when Oliver Callan took over his 9am to 10am show.
Tubridy was suffering from a persistent cough although it was hoped he would be back in time for the Late Late Show.
Speaking on RTE Radio 1 On Wednesday morning, Oliver explained: "Ryan has had a persistent cough over the last few days and he's getting it checked out so no need to worry.
"He's getting it checked out and hopefully he will be back on the Late Late Show this Friday, hale and hearty and doing what they've been doing over the last few weeks which I think has been very helpful to a lot of us and very entertaining as well."
However, with the star missing Friday morning's show there is increasing fears that he is not well enough to host the chat show tonight.
RTE confirmed the line-up for the show on Thursday but did not say whether Ryan would be involved or not.
International superstar Hozier will perform an emergency on-air appeal for the ISPCC on the show.
The Bray singer-songwriter will perform an exclusive set live in studio, promoting a new initiative between the ISPCC and RTE 2FM.
And Caroline O'Sullivan from the ISPCC will also be in the studio with advice for parents on how to deal with children who are struggling with the pandemic.
Former League of Ireland star Lee Duffy will also be on the show to talk about his harrowing battle with Covid-19.
The fit and healthy 28-year-old was hospitalised after he contracted the disease, and he will make an emotional plea to young people across Ireland to take the warnings seriously.
Meanwhile Mrs Brown's Boys stars Brendan O'Carroll and wife Jennifer Gibney will also be joining in via Skype link from Florida, as well as comedian Dara O Briain from London.
Two legends from the world of sport, Irish rugby hero Brian O'Driscoll and iconic GAA commentator Mícheal O Muircheartaigh, will also be on the show.
This special episode of the Late Late Show will air on RTE One on Friday, March 27 at 9.35pm.
