The Brown family leave Downing street in 2010Credit: Chris Radburn/PA
The Sun published a report in 2011 refuting allegations that his son's medical records may have been accessed for the story.
In evidence to the Leveson inquiry today, Brooks confirmed the article in 2011 that stated the source was a "shattered dad" whose own son had also been diagnosed was true, and that the Sun was "absolutely satisfied" this source got the information by "legitimate means".
Allegations that Fraser's medical records had been accessed were made against the newspaper in July last year.
At the time News International responded with a statement refuting the allegations and stating: "We are able to assure the Brown family that we did not access the medical records of their son, nor did we commission anyone to do so."
Today Brooks told the inquiry the story was discussed with the Browns "way before the Sun published it" in November 2006.
She said had the Browns asked her not to run the article back in 2006, she would not have done so.
“I spoke to the Browns, probably to people around them. I definitely had more of a conversation with Sarah Brown as she was my friend."
She said the information came to the Sun in late October and the Browns’ position at the time was "very much they had the tests confirmed" and that they "were committed to making this public.”
She added there was an “insistence that when the story was published, we highlighted the positives in association with the cystic fibrosis association.”
Asked if the source was paid, Brooks said she believed a donation was made to a cystic fibrosis charity.
She said the first time she heard of Brown's concerns relating to the source of the information was in 2011.
Brooks was questioned by Lord Justice Leveson about News International's response in print that this was a "smear".
Brooks responded that the combination of "the two attacks from Brown" which she said "had never ever been raised by him in any shape or form" previously meant the Sun "felt it was a smear".
"He was doing it five years later ... I think that's why they wrote the story they did".
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