My 13 year old has stained bottom teeth about half way up the teeth almost tracking the same line as her gum line. She is neurodivergent and hates tooth brushing but has become so self conscious. So 2 things, anyone found a good way to get neurodivergent teens to hate brushing their teeth (we already use a fruit flavoured toothpaste)? And how to get rid of the staining? Thank you