I need a good title for my book?

Silence... Breaking Silence.. Depends upon the book.

"Mute For a Reason"
"Silence"
"Dead Silence"

"Absence of Content"

"The Stillness"

"Void"

"The space between Words"

"Silent Squealer"

(No)

"Clam Lips"

(No)

"Dead quiet"

(Ye-No)

"The boy who watched their parents die, was traumatised, and never got over it and became a mute for the rest of his life."

(Ruins the entire story.)

It's about a boy with a bad past. He saw his parents die when he was just 8 years old so he stopped speaking to people all together

Are trumpets or drums mentioned in the book?

If not, this title comes to mind:  No Trumpets, No Drums.