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In the parent form, you can (optionally) add a field that will be used to store the ID of the child form. In this example, the field leave_details_id has been added. This is only needed in situations where there is a 1one-to-1 one relationship between the parent form and the child form. You can then embed your child form in the parent form by dragging the Sub Form form element into the section that you want the subform to appear in.
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