The reason that Blair's biological mother, Isabella, nor anyone else chose Dame Devin as a Lady Royal is because, despite passing the semester, the other students simply didn't think she was the right person for the job.
http://tvtropes.org/pmwiki/pmwiki.php/WMG/BarbiePrincessCharmSchool
FollowingWMG / Barbie: Princess Charm School
Go To
