Danielle Lloyd's son is undergoing tests for autism.
The 32-year-old model has always felt four-year-old Harry is "different" to his brothers, five-year-old Harry and George, two, so is having him assessed to see if he suffers from the lifelong developmental disability after having other possibilities ruled out.
She said: "I knew from when he was little that something wasn't quite right - it was mother's instinct.
"Now he's being tested for autism. Fingers crossed he'll be alright - I just have to keep an extra eye on him.
"Harry has been tested for so many things - including brain damage - after being born 10 weeks early.
"His MRI scans and ear tests were all clear but his balance is still not quite right and I know he's different to my other two boys.
"He's very much a loner and likes to be by himself rather than with the other two.
"He also struggles with things like getting himself dressed and playing games."
And Danielle - who has all three boys with ex-husband Jamie O'Hara - is hoping she'll be able to get Harry the help he needs.
She added in an interview with Britain's OK! magazine: "When I noticed these differences, I spoke to my health visitor, who suggested he might be on the cusp of the autistic spectrum.
"Hopefully more tests might show us other ways he can be helped if he does have a type of autism."