Star of the Sea by Una McCormack

Its name is Stella Maris, the 'star of the sea,' a small world beyond the edge of the human Expansion, where a few men and women - Vetch and human alike - have made their homes. Fleeing persecution or oppression on their own worlds, here they have found peace and plenty, in communion with the otherworldly Weird. A few weeks ago, that harmony was threatened, when Delia Walker came seeking hope for the future, hunted by her enemies in the Expansion, and went into the portal. Now, impossibly, her daughter has walked out, a grown woman, and demanded passage to the Expansion's capital. As more ships land on Stella Maris, bringing an end to the quiet obscurity the settlers have long cherished, a desperate race to carry Cassandra Walker to her destiny, and a resistance against those who would exploit Stella Maris for their own ends.