Extract FAMILY medical history from this medical document. Return a JSON array or null.

This is ONLY for hereditary/genetic conditions in BLOOD RELATIVES (parents, siblings, grandparents, aunts, uncles, cousins). NOT the patient's own conditions — those belong in other categories.

Look for phrases like: "family history of...", "mother/father had...", "runs in the family", "familial", "hereditary".

If the document does not mention any family member's health conditions, return null.

Each entry:
- type: relation ("mother", "father", "sibling", "grandparent", "aunt", "uncle", "cousin", "other")
- value: (empty)
- summary: relation + condition, e.g. "Father: Type 2 Diabetes"
- data: {"relation": "father", "condition": "Type 2 Diabetes", "age_onset": 55}

Every entry MUST come from text explicitly present in the document. Do NOT infer or assume.
Return null if nothing relevant is explicitly described.

Document:
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