There's been a lot of talk of PB being older than she seems, but has anyone thought she might be younger?

Now based on bits and pieces we've seen from promo art and flashbacks, PB was still lookin like her 18 year old self back when both Flame Princess and Princess Cookie were kids. But it's probably only been about 9 years since what happened in that Flame Princess promo art went down since FP looks about 5 in the picture and we don't know how old Princess Cookie is. So PB probably formed or was created at the age of 18 but for all we know, she could be 9 or she could be 1000. Just wanted to put that out there. Discuss.