inheritance and foreign keys

I was reading about inheritance and it occurred to me that this was what my
DB design needed. I had been creating mini-tables that perfectly applied as
child tables to other tables. So I set out to implement it.
Of course I am using primary and foreign keys and I thought it was odd that
it was not possible to REFERENCE my FKs to my PKs. So I started to give my
child tables their own PKs back. (I had taken them out, convinced I was not
going to need them anymore. The PK was supposed to be in the parent table)
Great, this approach seemed to work. Now I'm starting to populate my tables
and I stumble over yet a new problem. When I create an entry in a child
table and I go over to look to the parent table, it is there. When I try to
reference this entry in the parent table from yet another table, it comes
to tell me it doesn't exist. I don't want to have to reference it in the
child table. That would defeat the entire purpose of having chosen this
approach.
I wonder why this database is called Object Relational if this concept is
noet able to work properly with PK and FK relations. And I mean: out of the
box. I found ways to make my own triggers, but I don't have time to extend
the functionality of the DBS.

Abandoning this approach again and going back to using PostgreSQL strictly
as a RDBMS.

Jo