Petero

Nagato's elderly father who appears only in the TV series.

After Hyoh kills his son, he also orders the destruction of Nagato's village and family. Petero is wounded by one of Hyoh's soldiers while trying to save his two grandsons, until they are rescued by Kenshiro and Shachi. After being taken to safety, Petero finds his wounds aren't fatal and looks after Nagato's boys.

(Source: Hokuto Wiki)