Relationships Between Valar
Ilúvatar brought the Valar (and all of the Ainur) into being by his thought, and may therefore be considered their father. However, not all of the Valar are siblings; where this is held to be so, it is because they are so "in the thought of Ilúvatar".
It was the Valar who first practiced marriage and later passed on their custom to the Elves; all the Valar had spouses, save Nienna, Ulmo and Melkor. However, only one such marriage among the Valar took place within the world, that of Tulkas and Nessa after the raising of the Two Lamps.
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