Theoretically she can seek another entry in October. However, entry cannot be guaranteed. The POE officer may give her a hard time for returning so soon after a recent six month stay. The inspector may even deny her entry and send her back. Think of it this way, if she spends more than six months in a rolling 12 month window in the US, is she "visiting" the US or "living" in the US? That is how the POE inspector may think.