The Family Across the Street by Nicole Trope

Everybody wants to live on Hogarth Street, the pretty, tree-lined avenue with its white houses. The new family, The Wests, are a perfect fit. Katherine and Josh seem so in love and their gorgeous five-year-old twins race screeching around their beautiful emerald-green lawn.
But soon people start to notice: why don’t they join backyard barbecues? Why do they brush away offers to babysit? Why, when you knock at the door, do they shut you out, rather than inviting you in?
Every family has secrets, and on the hottest day of the year, the truth is about to come out. As a tragedy unfolds behind closed doors, the dawn chorus is split by the wail of sirens. And one by one the families who tried so hard to welcome the Wests begin to realise: Hogarth Street will never be the same again.