Quote 1
Welcome to the beautiful Sinclair family.
No one is a criminal.
No one is an addict.
No one is a failure. (1.1-4)
True to the title, Cadence starts the book by lying. All the Liars become criminals, Cadence is arguably an addict, her aunts drink constantly, and none of them can finish college or stay married.
Quote 2
That June, summer fifteen, Dad announced he was leaving and departed two days later. He told my mother he wasn't a Sinclair, and couldn't try to be one, any longer. (2.16)
We're with Dad—bail on that Sinclair business while you can. Bummer about sacrificing your kid, though.
Quote 3
Penny, Carrie, and Bess are the daughters of Tipper and Harris Sinclair. Harris came into his money at twenty-one after Harvard and grew the fortune doing business I never bothered to understand. (3.1)
Cadence is largely unaffected and unimpressed by Harris's wealth—except, of course, that her life would be very different without it. Oh hi, private island.