She was in quite a few TV roles (I think) during the 1970s. Her defining trait was that she didn’t age as most people do (due to disease or genetic defect or something), so she was playing kid roles well into her late teens. I remember she had chubby cheeks, too.
Not much to go on, but hoping you folks can scare up the name. Wife and I Googled until our fingers bled to no avail.
Dana Hill was who I thought of, too. I remember a photo in some cheesy celebrity magazine that showed her driving her car with the license place, “OVER 16” because she looked so young. Didn’t she die at a tragically young age?