It would appear that the mentor spirits can be assummed in some form to be related to the passions as per below
SM pg 40
THE PATH OF THE WHEEL
(Snip)
According to path doctrine, enlightened spirits follow a curriculum
in life, intended to move them further along the Mes ti
Draesis, the five great paths that form the Great Journey of the
Wheel of Life. Each represents a lifelong vocation associated with
an Order of Tir society, an element of nature, and a province of
Tír na nÓg. Each path also aligns with one of five metaphysical
archetypes known as Passions, typically represented by appropriate
mentor spirits.
The five paths are: The Path of the Warrior (for a mentor
spirit, use the Wise Warrior archetype), also known as the
Order of Cu Chulainn; the Path of the Steward (use the Great
Mother mentor archetype) or the Order of Etain; the Path of
the Bard (use the Fire Bringer mentor archetype) or the Order
of Brigid; the Path of the Druid (for mentor archetype, combine
the description of Owl with Moon Maiden’s advantages
and disadvantages) or the Order of Ogma; and finally the
Path of the Rígh (use Sky King) or the High Order of the Sun,
Moon, and Stars (reserved only for the Tir elite and believed to
possess exclusive metamagics able to replicate all the advantages
of the lesser paths).