The telly presenter, 38, left a rather awkward response after James, 42, announced his father has terminal cancer.
James addressed his 226,000 Instagram followers with the heartbreaking news.
He explained that he initially thought his father, William, had suffered a stroke.
However, after extensive medical tests, it was revealed that he has incurable cancer.
James' post continued: "It was what I had dreaded, my dad has a tumour and after having a biopsy it’s come back that it’s an aggressive cancerous one.
"It was what I had dreaded"
"The worst kind unfortunately. We have been told that it’s not advisable to operate because of where the tumour is and wouldn’t actually make that much difference even if they could.
"The end result is, it’s terminal."
Joe responded by remarking how much better William is apparently looking.
He wrote: "This vid is amazing!! It So good 2 see your dad doing better xxxxx."
"This vid is amazing!!"
Several of James's fans worried if Joe hadn't read the post, and instead simply watched the video component.
In the video William is shown playing with James' bay daughter, Ella.
One user commented: "Joe I think you best read what James has written."
Another remarked: "I'm sure you'd never mean to cause offence but his Dad isn't doing better, quite the opposite if you read the post."
And a third explained: "Mate his dad is really poorly."
And a fourth elaborated: "His dad isn’t “doing better” he has just been diagnosed with an aggressive brain tumour. Read the post properly...."
Meanwhile many other celebrities offered their condolences and support to James.
Peter Andre posted: "So sorry mate. Please stay strong. Here if you need us."
Coleen Nolan wrote: "Oh god James i’m so so sorry! Thinking of you all ! I have Everything crossed for you in finding someone to help! Sending the biggest virtual hug possible! xxxx."
Nicola McLean commented: "I’m so sorry sending all my love to you all."
And his former Strictly colleague Shirley Ballas commented: "I’m soooo sorry thinking of you all at this time."
*ED! has contacted Joe Swash's representatives for comment.
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