Why is this sub-category as high as it goes, age-wise, within the main "Parenting" category?

Why is there no "Young adults" sub-category on here, for parents of young adults and late teens who are just about to enter into adulthood, and for these late teens and young adults, themselves? 'Cos I think you'll agree that adulthood's a bloody big and bloody scary next step for anyone to take, regardless of who they are, and I'm bloody sure those who've just entered into adulthood, those who are about to become adults and their parents and guardians have probably got plenty of questions, with regards to this, at times, treacherous minefield called 'adulthood'. I definitely did have, as I hit it.