conditional dropdown for field that displays value from another field

I have 2 table Family and Individuals. Family and Individuals have one to many relationship (Family<Individuals). Family has fields name(user input text) and typeX (text multiple choice yes/no). The field name is shared value. Table Individuals has field Part, which is value from field- "name" of Table Family. Although there is parent child relationship and each record in Individuals is linked to parent table family, we should add a records in family which is not parent record. In the drop down I should only display records of shared field- "name" that has typeX as yes. 
Please guide me on how to do it.

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Aswin Babu
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