A Frost Untimely — Phaedra Weldon

This is a novella which takes place between Ill Met By Moonlight and Rest Ye Merry Gentlemen. Melody Blackstone wants a greenhouse built next to her shop. Enter Riley Pritchard. He's polite, sweet, tall, handsome… And Mildred Thumper's nephew.  But as Mildred's fight to prevent her nephew from getting involved with a Blackstone begins, the Blackstones and some of Castle Falls' citizens notice there's something wrong with Mildred, something only the magic of the Blackstone Witches, and Mildred herself, can cure. The Blackstone Witches is a series of novellas highlighting each of the Blackstone children.