Permalinks & Categories

I have a post that is listed under the category “music” and I want to be able to create child categories of music with musician names. If I select both the parent category “music” and the child category “Sarah McLachlan” my permalink (currently set to /%category%/%postname%.htm) shows this:

mydomain.com/music/sarahmclachlan/the-post-title.htm

Is there a way to only show music in the permalink? (and not the child category?)