[maternal grand-parents], strici in tete

- x x
- x x
- - x x
    └ x x
    3
  - x x
  - x x
  - x x
    └ x x
    2
  - x x
    └ x x
    1
  - x x
- x x
- x x
- x x
- x x

x x

  

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x
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