Within the FindChild method, no, as far as I know there is not.
HOWEVER... if you use NameMapping and employ the conditional mode, then yes, you can. (see
http://smartbear.com/support/viewarticle/12852/)
This requires you to do some more work up front in mapping out your components, but it is possible to do this with NameMapping.
If you prefer not to, what you would need to do is employ two "FindChild" statements and then call the "Exists" method off the resulting objects and do a check to determine which one is the one that is actually used.