Yes, there is an easy  way, but I'm not sure its what you want. If you
select to not have the site  inherit the top  bar of the parent than that
site becomes the Home tab of the top bar. That has the side effect of
removing all the other peer sites  from the bar since you are not
inheriting the top level  anymore. Otherwise, the top level site of the
inheritance is always the Home tab on the Nav bar. To change  that would
require creating your own custom Nav bar provider. Although that is
do-able, its not something that would be considered particularly easy.