When you think of Beethoven you think of Ludwig, the famous musician, not his father.
When you think of Obama you think of Barack, the famous president, not his wife.
When you think of Putin you think of Vladimir, not Igor his cousin.
Of course you think of the famous person, wtf is the point of this post.
Or Percival, Kendra or Ariana
Well yea cause he is a authority figure in their school. Usually you call teachers and the sort by their last name not their first name.