How to generate unique IDs with XML Source to OLE DB Destination inside Foreach Container

I have a Data Flow Task that contains an XML Source which writes to a SQLServer database.

It writes as expected with a single source file. 

In a Foreach container it writes multiple files as expected...

...however the auto-generated record IDs reset on each iteration of the Foreach container, creating duplicate ids instead of uniquely identified rows.

e.g., file #1 is processed and IDs 1, 100, 200 are written to tie the OLE DB destination tables together.  Then file #2 is started, and the IDs 1, 100, 200 are reused and the table relations are no longer valid.