Dynamic picklist based on a form with a deeper form.

Dynamic picklist based on a form with a deeper form.

Hello,

I have 4 forms:

1. Form with single line named: Label 1
2. Form with single line named: Label 2
3. Form with single line named: Label 3

4. Form with three look-upfields based on forms with Label 1, Label 2 and Label 3

5. Form with three look-upfields based on form 1, 2 and 3.

Now I want to make the lookupfields in form 5 dynamic.
So if in form 5 label 1 is chosen it only has to show the relevant labels 2 based on form 4.

I hope someone can help me.

Greatings,

Erwin.