Beyond the Glen by Diane Haeger
As children, half-sisters Colleen and Mairi Gordon grow up in a small hamlet in Scotland with their often brutal father and Mairi's French mother. When Vivienne could no longer bear the way she and her daughter were being treated, she took Mairi, renamed Marielle, to Paris to live. The sisters vowed to stay in touch through letters. Marielle received none from her sister and heard only that she had married.
After 20 years Marielle, now a journalist, returns to Scotland to find the sister she loves, the past she lost, and the fulfillment of her destiny. But Marielle's cherished hope for a reunion is shattered when she discovers Colleen was the victim of a mysterious accident. Determined to uncover the truth, Marielle returns anonymously to the village and turns to two men--one of them her sister's husband, the other a childhood friend--who will link the secrets of Colleen's life with her own in this powerful, evocative tale of heartbreak and love.
The ISBN and cover below do not match. The cover is from later edition while the ISBN is for the first 1998 edition which I have before me.
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