Polyanna, Youngest Sister

Polyanna can help against Commander O’Neil before appearing among Millicent’s sisters in Elphael. Her early cooperation is optional.

Locations and access

Caelid · Heart of Aeonia summon

Starting Site of Grace: Inner Aeonia

Speak to Gowry in the shack south of Sellia and agree to retrieve the needle. Travel west into the swamp to Inner Aeonia.
Look south of the grace among the large pale roots for Polyanna’s gold sign before entering Commander O’Neil’s clearing.

Elphael · Millicent’s final battle

Starting Site of Grace: Drainage Channel

From Drainage Channel, backtrack west through the tunnel and climb the ladder. Leave through the western doorway, then turn right up the northwestern slope and clear the pest at its crest.
Turn south-southwest onto the large root crossing the pit. Drop from its end toward the isolated Scarlet Rot pool. An Ulcerated Tree Spirit appears when you approach; this is the enemy needed for Millicent's final signs.
Defeat the Tree Spirit, rest and return to the high ground above the pool's northwestern edge. The gold sign helps Millicent against her four sisters; the nearby red sign challenges her instead. Read the prompt before confirming.

Quest steps can include different outcomes. Read the branch, conditions and cutoffs before making a choice.

Optional needle assistance
Branch: Main quest
Summon her against Commander O’Neil after accepting Gowry’s request. Defeating the boss gives the needle regardless of whether you summoned her.
Later sisters encounter
Branch: Main quest
At Millicent’s final choice, Polyanna is one of the four sisters opposed to Millicent. Choose the gold sign to help Millicent, or the red sign to fight against her.

Reward or service	Condition	Details
Commander O’Neil assistance	Use Polyanna’s gold sign.	O’Neil awards the Unalloyed Gold Needle and Commander’s Standard. Polyanna does not hand them over herself.

She appears as Polyanna, Adopted Daughter at the early summon.
The early sign is tied to Gowry’s request and disappears once its boss is dead.
She uses Blade of Calling, but her summon does not award that weapon.
Her later hostile role does not undo the earlier needle reward.
Do not confuse Commander O’Neil in the swamp with Commander Niall at Castle Sol.