Ronan Keating has reacted to his eldest son Jack Keating 's announcement that he has become a father, amid fans congratulating the family on the new arrival.
Jack, 23 - who appeared on Love Island last summer - took to Instagram on Thursday night (March 9) to announce the birth of his first child, whose name hasn't been revealed.
The reality TV star shared a black-and-white photo of himself cradling the newborn baby, with him writing in the caption: "Welcome to the world my little [princess emoji]".
The post has amassed thousands of likes on the platform and prompted comments from Jack's followers, including a responses from his own well-known dad Ronan, 46.
Ronan - who shares his three eldest children, including Jack, with his ex-wife Yvonne Connolly, 49 - wrote in the comments section: "Little cutie". He added a heart emoji.
Ronan Keating’s son says Love Island quizzed him on his dark sexual fantasiesThe newborn is understood to be the former Boyzone member's first grandchild, prompting messages of congratulations in response to his comment on Jack's post.
One person wrote in a reply to the father-of-five Ronan in the comments section of Jack's post: "Big congratulations on becoming a grandad. It's the best feeling in the world".
Another wrote: "Congratulations on becoming a grandad. You must be very proud." Whilst a third person wrote: "Congratulations to you all. Such wonderful news".
Ronan - who shares his two youngest kids with his second wife Storm Keating, 41 - wasn't the only relative to comment on Jack's announcement on the platform.
The former islander's mother Yvonne also reacted to the post. She wrote in the comments: "I miss her so much already". The mother-of-three used several heart emojis.
A comment was also left by Jack's step-mother Storm - who has been married to Ronan since 2015. She took to the comments section to share red heart emojis in response.
Jack's relatives were among those who reacted to his post on the platform this week, with some of his former co-stars from last year's Love Island having also commented.
This included congratulatory messages from finalists Paige Thorne, 25, and Luca Bish, 23, as well as other co-stars like Danica Taylor, 21, Chyna Mills, 24, and Billy Brown, 24.