Unpredictable Events — Cecilia Peartree

This is the 13th book in the Pitkirtly Mystery series, set in a fictitious small town on the Fife coast in Scotland. Not a million miles from Culross, and yet rather different from it.
Christopher finds that going away on holiday is a lot more trouble than it's worth, while a wedding in the Cultural Centre isn't without its problems. Amaryllis tries to keep a low profile as she teases out secrets from the tangled threads of everyday life, and Christopher's sister Caroline allows obsession to lead her into danger.