The parent term(s) for this term.
This property is not loaded, but may be used to modify the term parents via Term::save().
The property can be set to an array of term IDs. An entry of 0 means this term does not have any parents. When omitting this variable during an update, the existing hierarchy for the term remains unchanged.
Type: \Drupal\Core\Entity\Field\FieldInterface
public $parent;