Boyzone singer Ronan had posted pictures on social media of their son Cooper in a hospital bed and wearing an oxygen mask, saying he and his wife Storm were "worried sick".
Storm has now posted an update on Instagram, saying that everyone's prayers must have worked because Cooper was doing better and was headed home.
Sharing a picture of the little boy cuddling a stuffed animal while in hospital, she wrote: "48hrs we are happy to see the back of.
"Thank you to everyone for your prayers and well wishes - they worked (!) because our little man is on the mend and on the way home too."
The relieved mum also thanked the "wonderful staff" at Chelsea and Westminster Hospital, saying they had been "simply amazing".
"This mummy is exploding with joy and relief to be bringing @cooper_keating home with daddy," she added.
Earlier this week Ronan said the couple were a "mess" but that Cooper had been "an absolute trooper”.
The 44-year-old didn’t elaborate about his son’s condition.
Fans and friends of the couple expressed their relief after Storm shared her update.
"Sending so much love to you all," wrote Kirsty Gallacher, while Ore Oduba posted a string of heart emojis.
"So happy for you, nothing worse than your child to be poorly and you feel helpless," said one fan.
Cooper is Ronan’s oldest child with Storm. The couple – who tied the knot in 2015 – also have a one-year-old daughter named Coco. The singer also has three children from his previous marriage.
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