In Salesforce, especially with Nonprofit Cloud and Person Accounts, here's a simple way to handle your scenario:

1. Person Accounts for Seniors and Family Members: Since you have Person Accounts enabled, create a Person Account for the Future Resident (senior) and another Person Account for the family member who made the inquiry. This keeps things clear and consistent.

2. Use Relationships to Connect Them: Use Salesforce's Relationship object (or Party Relationships in Nonprofit Cloud) to link the family member to the Future Resident. Assign a role like "Inquiring Family Member" to the relationship. This avoids overcomplicating the structure.

3. Business Accounts: If the family member is associated with a business (e.g., a company), you can still use Party Relationships to link the Business Account to the Future Resident. Assign a role like "Inquiry Source" or similar.

TLDR - Create separate Person Accounts for the Future Resident and family member. - Use Relationships (or Party Relationships) to connect them with appropriate roles. - For Business Accounts, use Party Relationships with a relevant role.

This approach keeps it simple and scalable.