Whispers in the quiet town

Five children. Five homes. Five identical murders.
In a town where nothing bad ever happens, the brutal deaths of five six-year-old children shatter the peace. There are no signs of forced entry, yet every child was murdered in their own home with the same knife, the same wounds, and exactly five minutes between each death.
But Sam, the seven-year-old son of the town’s chief of police, discovers something the investigators don’t want anyone to know.
His mother knows who the killers are.
And she intends to keep it a secret.
Until Sam discovers the truth and becomes the next secret to be buried.