A Pang is more conspicuous in Spring — Blue Bird Prince

A Pang is more conspicuous in Spring 1
In contrast with the things that sing
Not Birds entirely-but Minds-
Minute Effulgencies and Winds-
When what they sung for is undone 5
Who cares about a Blue Bird's Tune-
Why, Resurrection had to wait
Till they had moved a Stone-
(F.1545/J.1530)
[1–8]:: This poem is about the fairy tale Blue Bird by Madame d'Aulnoy.
[1] Pang:: Princess Florine and Prince Charmant were separated by the evil queen and fairy Soussio.
[3] Minds:: Prince Charmant was turned to a blue bird, and talked to Florine only at night.
[6] Blue Bird:: a hint on the answer.
[7] Resurrection:: returning of the prince to his human form.
[8] moved a Stone:: an obstacle, magic that kept them apart.

"You may stone me to death, you may flay me alive," cried the king, "but I will marry no one but Florine. I am resolved. You many therefore exercise your power upon me as you please!" . . . screamed Soussio, passionately; "you may fly out of that window if you like, for you shall be a Blue Bird for the next seven years!" ─ Fairy Tales by The Countess D'Aulnoy, translated by J. R. Planche (1855)