Being a wife and mother is can certainly be a very satisfying career choice for a woman. Speaking as a woman with a satisfying career, the happiest time of my life was when I was able to stay home with my infant son for his first year of life. While I value my career and find it personally satisfying, the main reason I have worked outside the home has been to support my family, not for the personal satisfaction it brings. If my husband was wealthy, I would not work, though I would likely continue my education because that's something I enjoy. If this man makes your sister happy, then be happy for her being able to make that choice. It's not on option for every woman.