A fatal fleece : a seaside knitters mystery / Sally Goldenbaum.

Enhanced descriptions from Syndetics:

Readers can't help but get entangled in this  USA Today  bestselling series.

It's summer in Sea Harbor, Massachusetts, and while tourists flock to the beautiful cottages by the sea, trouble brews for the Seaside Knitters.  One of them gets tangled up with a precocious granddaughter and another stands accused of casting a local resident off on a permanent vacation.

As Izzy Chambers and the Seaside Knitters prepare Izzy's yarn studio for the tourist season, fellow knitter Birdie Favazza has her hands full with a visiting granddaughter she never knew existed. Gabby soon becomes a fixture in the town--riding off on Birdie's bike, teaching her own crochet class, even striking up an unlikely friendship with a reclusive local fisherman named Finnegan, himself the source of much local turbulence.

But it's Cass Halloran, the lobsterwoman, who stumbles over the body of the old fisherman, covered with leaves and sea grass, and wearing the yellow fleece vest she once made him. When Cass unwittingly becomes a suspect in his murder, the knitters rally to protect their dear friend.

Soon the Seaside Knitters will discover that caring for Gabby while casting their net for a killer is tricky business indeed.  They'll have to keep their wits about them as they piece together the clues, working to catch a killer before one of their own winds up knitting behind bars.