I've never read a book by Natalie Standiford before, but everyone I know who's read them has told me great things about them, so I had high expectations. And I was not let down.
The writing style was light and breezy, easy to read, and engaging. The majority of the book's written in the form of the three sisters' (Norrie, Jane, and Sassy) letters to their grandmother, and so it's written in the casual way you would talk to someone. With the story told through letters, I was concerned I wouldn't get to the characters' heads and miss out on a lot of the plot, but neither of those happened.
The characters were realistically developed. All of them had a unique voice and personality that made her letter easily distinguishable. Their confessions each are genuine, thorough and heartfelt.
The ending was probably the only downside for me. It was kind of anti-climactic, even though I did guess it from the wording of the synopsis. "...her (or his)..."
I give Confessions Of The Sullivan Sisters a 4 out of 5.