Sometimes you need to keep a few secrets. Frankie knows she'll be in big trouble if Dad discovers she secretly posted a dating profile for him online. But she's determined to find him a wife, even if she ends up grounded for life. Frankie wants what she had before Mom died. A family of three. Two is a pair of socks or the wheels on a bicycle or a busy weekend at the B&B where Frankie and Dad live. Three is a family. And Frankie's is missing a piece. But Operation Mom is harder to pull off than Frankie expects. None of the Possibles are very momish, the B&B's guests keep canceling, Frankie's getting the silent treatment from her once best friend, and there's a maybe-ghost hanging around. Worst of all, Gram and Dad are definitely hiding secrets of their own. If a smart cookie like Frankie wants to save the B&B and find her missing piece, she's going to have to figure out what secrets are worth keeping and when it's time to let go.
Along with her best friend and neighbor, Elliot, she tries to figure out how to save the day and what she feels is left of her family. After her mother died when she was four years old, it hasn't felt quite whole enough for her, despite her maternal grandmother (Gram) moving in and being there for Frankie and her father. Now that years have passed since she lost her mother, her father is mysteriously even more busy than usual much of the time, as is Gram, and Frankie and Elliot are doing what any pre-adolescents would be doing - looking for something to occupy their time. They (mostly Elliot, but Frankie goes along for the ride) dabble in looking for ghosts, which seems to be a big reason why the bed and breakfast is not doing so well, since people are under the impression that the place is haunted, leading Frankie to believe their business and home is in a lot of trouble since town bad guy Reggie always seems to be lurking and waiting to snatch up the B&B the first chance he gets.
As the story continued, the feeling of family that Frankie felt was not necessarily around is obviously there, despite her not noticing it, lending an 'It's A Wonderful Life' style vibe. Her relationship with ex-best friend Jess seemed believable, as kids are always going in and out of friendships, but it was never really explained what happened with them to begin with, beyond Frankie and Elliot's own speculation on the matter. However, the family and friends vibe, coupled with the idea that things can work out even when you least expect them to, makes the predictability of 'Smart Cookie' something that readers can be okay with, since it's sometimes nice for things to work out just the way one expects, but with a few twists and turns along the way for good measure.