Stitching two LDAP databases together using chaining?

Hi,

Let's say I have a database with base DN dc=parent. On a particular server, dc=parent is a read-only syncrepl slave.

On the same server, I have a separate read-write database, dc=child,dc=parent.

Is there a way to make it so searches of dc=parent also search the database in dc=child,dc=parent?

I'm thinking a referral plus the chain overlay might do the trick, but I can't create a referral object with name "dc=child,dc=parent" within the dc=parent database because the server knows dc=child,dc=parent already exists (as the other database). I get "Already exists (68)" from the server.

I figure I'm missing something simple, or doing something stupid.

Thanks, Mike