Is questioning the lineage of a family considered an impugnment of lineage, and is tracing lineages with the intention of severing kinship ties forbidden?

Differentiation in the sight of Allah Almighty is based on faith and piety. Boasting about lineages and disparaging them are matters of the pre-Islamic era (Jahiliyyah), and the Prophet, peace and blessings be upon him, warned against them. It is not permissible for a person to claim a father or a tribe other than their real father and tribe. Nor is it permissible for them to deny their lineage from them. It is permissible to learn about lineages to strengthen bonds and maintain kinship ties. People are entrusted with their lineages, so it is not permissible to disparage anyone's lineage except with legitimate proof, and the purpose should be to maintain kinship ties and relations, not to sever them or to gloat.