The Petreference field stores the pid of a related pet template. The title of the related node is usually displayed as the value of this field.

The Petreference field can use an autocomplete widget, or, when used with Optionwidgets, the available values can be presented to the end user in a drop-down select list, checkboxes, or radios.

A Petreference field can be used in Views to create a Relationship to another node, to allow you to use any field, argument, or filter from the related node in your view.