The Song of Delphine has already received a couple of nice reviews, one from The School Library Journal and another from Kirkus Reviews.
You can't read the full School Library Journal review at their site unless you are a subscriber, however Barnes and Noble has the review in full. Here is the gist:
Text and watercolor and ink illustrations combine wonderfully in this story... The giraffes are full of personality, and children will enjoy hunting for them and their companions, from the stunning endpapers done in black ink strokes and dots to the pages within. ... Don’t miss this story of the power of music to bring joy and comfort even in trying times.
The full Kirkus review is here. The quotable version is below:
Kraegel creates minutely inked watercolor elements—trees, grasslands—as backdrops for simply contoured humans with brown skin, naturally textured hair and bright clothing. As Delphine and Beatrice ride off atop two giraffes, readers of this quiet story will savor their new friendship.