No. You are implying that starving a child would lead to them "losing" fat cells in number. Without liposuction, fat cells aren't disappearing. Yes, childhood and adolescent obesity can lead to the production of more fat cells in number than there would be had they not been overfat.
Other than that, barring extreme fluctations in weight, you are pretty much stuck with the same number of fat cells. They will simply either be "full" cells or "empty" ones. Empty fat cells take up little space.
As far as this topic, however, getting down to 8% body fat isn't impossible. There is the issue of further progress. Very few people could actually make further progress in terms of muscle mass while maintaining a body fat percentage that low. 12% isn't "fat" and actually makes me wonder just how out of shape you think you are.
There have been plenty of guys on these boards acxting as if they were on the verge of obesity when in reality, they were just short of "skeletalization".