Mr. Volney has an enormous fortune. He is, as you say, a senile old man in his dotage. As you say again, such a marriage is a travesty. But Elise is incapable of feeling the love which alone renders marriage a holy institution. She has undesirable qualities which ought not to be transmitted to children, and she is absolutely devoid of maternal instincts.
I have heard her say she would consider motherhood the greatest disaster which could befall her. But she is unfitted for a self-supporting career, and she wants a home and position.
She has beauty, kind and generous impulses, and a love of playing Lady Bountiful. It is not so much that she wants to benefit the needy, as that she likes to place people under obligations and to have them look up to her as a superior being.
Old Mr. Volney is a miser, and his money is doing no one good. He has only distant relatives, and by taking Elise for a wife (according to law) he will wrong no one, and she will make much better use of his fortune than his heirs would make.
Your mother will be relieved of worry and care. Many worthy poor people and charities will receive help, and Elise will have her heart’s desire—fine apparel, jewels, a social position, and no one to bother her. The valet and nurse will look after Mr. Volney, and his simple old heart will bask in the pride of an old man—the possession of a pretty young wife.
Had he full use of his mental faculties, and did he long for love and devotion, I would try and dissuade Elise from the marriage, but solely on his account, not on hers.
The young man you mention, as your choice of a suitor for the hand of your sister, might better go up in a balloon to seek for Eutopia than to expect happiness as her husband. He has a sweet, gentle, loving nature, a taste for quiet home joys, fondness for children, and he has two thousand a year, with small prospects of more in the near future.