Circle of Magic/Heartwarming

"Briar: It's us! All: It's always us."
 * Briar's reasoning behind the date he chose for his birthday at the end of Briar's Book/The Healing In The Vine. "The girls would be vexed at having so little time to prepare, but they would adjust. They would know, as he did, that his life began when Rosethorn had invited him into her world."
 * The last lines of the last book. Briar explains the little mind palace created for the four in his dreams.