Among the German: Blood Vengeance. Right that Sippe had (family, clan, family collective) to persecute and avenge a death of a relative, murdering the one who committed the murder.
Germanic name for the Revenge of blood that was common in primitive peoples without a legal system, where a family could charge a crime to one of their own by executing with impunity the murderer or someone of his family. Today Blutrache (pr. Bltraje) can simply be translated as revenge.