Perhaps the makers of this uneven comedy-drama thought that using the same word in the title might secure their picture as much success as it did “Little Miss Sunshine.” But surely they’re mistaken. “Sunshine Cleaning” has a good cast, a cute kid and some bright moments. But it’s just a pale reflection of the earlier film, an attempt to air a similar message about the importance of family that has neither its laughs nor its poignancy.

At the center of the Albuquerque-set story are the two Norkowski sisters. Rose (Amy Adams) is the responsible one, working on a cleaning crew while raising her adorable but precocious son Oscar (Jason Spevack). But she’s also having an ongoing affair with a married man, a police detective named Mac (Steve Zahn). When she’s off with him, she has Oliver babysat by her free-spirit sibling Norah (Emily Blunt), who lives with their dad Joe (Alan Arkin), a salesman always on the look for a get-rich scheme who can also watch Oliver in a pinch (as when the lad is expelled from school for being disruptive).

The plot kicks in when Mac suggests that Rose consider going into the crime-scene business, cleaning up in both senses of the phrase. She runs with the idea, enlisting Norah as her partner. Bumbling through their first jobs, they soon learn that there are rules and regulations they must follow, courtesy of helpful one-armed supply clerk Winston (Clifton Collins, Jr.). And they work toward the goal of securing assignments from insurance companies, where the big bucks are.

Interwoven with this plot are the more personal ones. Rose labors to get some acceptance from her old high school classmates while reconsidering her affair with Mac. Norah, haunted by the suicide of their mother, is moved by the death of a woman whose house they’re called upon to clean and strikes up a relationship with her estranged daughter (Mary Lynn Rajskub). And Joe, trying to score big, buys a load of fresh shrimp to sell at a profit, while taking little Oliver along for the ride. Of course, nothing turns out as planned for any of them, or for Sunshine Cleaning when an insurance company at last calls.

There are moments here that are funny and/or moving. Arkin’s interaction with Spevack—a charming wide-eyed kid—is familiar but still enjoyable. Adams and Blunt play off one another well, and do a nice routine in their early “clean-up” scenes. Adams has a fine moment when she commiserates with a woman whose husband has committed suicide. And the laid-back Collins underplays pleasantly.

But too much of “Sunshine Cleaning” meanders limply along under Christine Jeffs’s uninspired direction, longing to say something insightful about the need to come to terms with death but never quite succeeding. And while trying to seem down-to-earth and authentic, it keeps stumbling into narrative mistakes. At one point Rose needs somebody to watch Oliver and impulsively leaves him with Winston, a man she barely knows. And she thereupon goes off to a baby shower with the women she’s seeking acceptance from—but without bothering to bring a gift. Does scripter Megan Holly even know what a shower is for?

With a grungy look courtesy of designer Joe Garrity and cinematographer John Toon and irksome musical interruptions by Michael Penn, “Sunshine Cleaning” comes across as a festival film par excellence—one that withers when removed from that special Sundance atmosphere.