Key legal question
Whether the mother could appeal alone against the judgment upholding the paternity challenge despite necessary joinder with the child.
Extracted holding
Yes. In paternity challenge cases, the mother or the child may each appeal alone; Art. 70 ZPO does not require both to appeal together.
Extracted reasoning
The decisive point is that substantive law determines when joint action is required. Under Art. 256 ZGB and prior case law, the mother-child relationship is a special status dispute with potentially conflicting interests and an indivisible judgment effect, so the established exception survives the ZPO.