Working Murder (1989)

Amazon.com Product Description (ISBN 0804108137, Mass Market Paperback)

Clara Gamadge puts down the phone with a tremor of excitement. Only a year ago that call would have come to her husband, gifted sleuth Henry Gamadge. Now Henry is dead, and Clara is summoned to deal with the latest convulsion in an old family tragedy.
Haunted by the never-explained disappearance fifty years ago of her lovely daughter, Ellen, Clara's Aunt May ignores a kindly anonymous letter advising her to let Ellen rest, or live, in peace -- and suddenly dies. And so begins Clara's first solo case, a tragic, twisting tale that winds far into the past -- back to Prohibition, bitter family feuds, secret love affairs, and a cherished, laughing girl.
In this lively puzzle, author Eleanor Boylan, whose own aunt Elizabeth Daly, wrote eight Henry Gamadge mysteries, does her aunt -- and her readers -- proud.
"[A] charming contemporary mystery in the classic mode." -- The Washington Post Book World