This tragic tale in verse struck all the right chords with us.
Madrigal "Maddie," Aria and Strum are all named after musical things, as their parents are music teachers (vocal and instrumental). But it's Strum, in college, who rebels first from their parental expectations. He walks away from his college dormroom one day and tells no one where he's going or what he's doing.
This sparks a downward spiral for the family and Maddie in particular, who has to deal with all the repercussions of her brother literally walking off the map.
Aria rebels by going out with friends and getting drunk. She refuses to share the contents of the last email she exchanged with Strum, a particularly cruel blow for her younger sister.
Maddie also has to navigate all the horrors of middle school with a missing loved one. She becomes known as the kid no one can talk about because someone in her family is missing. It's a bit much to bear, but she finds allies in unlikely places.
But in the end, it's Maddie who figures out Strum's disappearance is tied to his ecological and social justice beliefs, and Maddie correctly identifies what direction he's heading, even if the police assigned to Strum's missing person's case don't put much stock in what she says.
I won't spoil the ending, just know it's not terribly tragic and ends on a high note, appropriate for middle grade, even if it is perhaps a much happier ending than most IRL missing persons cases.