1. Create your eForm following the steps in this article: How does an Administrator create an eForm?.
2. After saving the questions and settings of your eForm, go to the Members tab. From there, select Dynamic Members and click the Choose Filter button.
3. In the Create Filter screen, select the appropriate Group/s under Select Groups on the left-hand side. On the right-hand side, under Additional Attributes select Request, followed by is the eldest in the family.