Mr. Marx's Secret by E. Phillips Oppenheim

That it was my mother I could not at first believe. She wore a plain dark dress, with a black lace kerchief about her neck; but a dress, simple though it was, of a style and material unlike any that I had ever before seen her wear. Although I knew nothing of her history, I had always suspected that she was of a very different station from my father's, and at that moment I knew it, for it seemed as though she had, of a sudden, made up her mind to assume her proper position. Not only were her dress and the fashion of arranging her hair unusual, but her manners, her voice, her whole bearing and appearance were utterly changed. It was as though she had, without the slightest warning, dropped the mask of long years, and stepped back, like a flash, into the personality which belonged to her.

Nor was this the only change. A slight pink flush had chased the leaden pallor from her cheeks, and her eyes, which had of late seemed dull and heavy, were full of sparkling light and suppressed animation. Her manners, as well as her personal appearance, all bore witness to some startling metamorphosis. I was more than astonished; I was thunderstruck. What seemed to me most wonderful was that a visit from the man against whom she had so solemnly and passionately cautioned me should thus have galvanised her into another state of being.