There does not appear to be any PMI rules against project management experience coming from a family business, provided that you meet all eligibility requirements (which may be difficult if your experience is limited to only 3 years). If you are eligible, you should put down your supervisor regardless of family status and be prepared for them to justify your work experience to PMI if audited.
For the past three years, I've been working for my family business where all employees are family members. My direct supervisor is a family member. Should I put my supervisor as my reference?
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