One to One Relations in Forms

[Pap]

Greetings,

I have the following tables:

1. Employee Table with these fields:
a)EmployeeID b)FirstName c)LastName
2. Employee Private Info Table with these fields:
a) EmployeeID b)Birthdate c)SSNo
3. Employee Expenses Table with these fields:
a)EmployeeID b)Insurance c)Training

I have a one to one relationship via the EmployeeID
fields from the first table to the second table and from
the first table to the third table.

I then create a form combining the first two tables and
it works out great.

I would like to create another form that has the Employee
ID as a pull down menu and enter entries for the third
table according to the pull down menu from the first
table.

I tried to do this with a combo box, but I get duplicate
entry errors and with other tries I pull down the combo
box, but it does not change the entries for the third
table! Thanks for any help