age has a tremendous lot to do with technical skill, extent of real-life observation, confidence (or arrogance), affluence with regards to culture, and many other things. Don't worry, Helm isn't a creep ^^.
my mother is a specialist in the field of disorders with expertise in high-functioning autism. If you want to be able to create characters, she suggests that you write down aspects of many different characters on little cards which you can mix and match at random for ideas, using that as a framework rather than relying on thoughts alone, then if you get used to this, you might be able to chose possible aspects from your memory, rather than "imagination". Many people who are not as hindered still find this a very beneficial practice for planning any kind of project. It's worth a shot, i think.
