Supplementary Provisions, Article 6
第六条
When a new family register is created for a person in a family register referred to in Article 3, paragraph (1) of the Supplementary Provisions, any child of that person who is in the family register referred to in that paragraph and who continues to have the same surname as that person joins the new family register; provided, however, that this does not apply if that child has a spouse or has a child in the same family register as them.
In the case referred to in the preceding paragraph, if the new registered domicile is designated within the same municipality as the locality of the previous registered domicile, the provisions of Article 30, paragraph (2) do not apply.