MDI database locks record on everyother edit?

To simplify, I have an MDI database app that uses two types of MDI
forms. One is a "browser" with a grid, add edit and delete buttons. The
other is an input form using TDBEdits. Both contain TTables set to the
same Datasource and Tablename. The table is a Paradox table.

When a user selects Edit, the Edit Child form is instantiated, and the
table is moved to the record indicated by the "browser" form with a
FindKey statement.

If the user attempts to editt the same record twice, a try-except  
structure around the edit statement is triggered and the exception is
trapped. A warning dialog is shown, and the child form is closed.

All of this is functioning as expected.  However, if the user then
atempts to edit the same record a third time, the exception is not
generated, and the except block from the try-except is not executed.
This occurs on every other subsequent attempt to edit the same record.

Any help is appreciated.