After Lehman Brothers went down, comments circulated on social media that if it had been a partnership of Lehman Sisters maybe greed wouldn't have gotten the better of it.

It isn't healthy to stereotype, and it may or may not be a useful exercise to study how many women have risen in investment banking and whether or not they do things differently from men. Certainly, whatever the investment style, in a competition for profitability one has to achieve results or else lose clients. But sustainable investing is proving that profits can come with a caring touch, and many women, and men, are excelling at it.

Here's one story of two women and their own quiet revolution.

Lily Engelhardt began a career in investing in 1981 and soon hired another Lily, LiliAnn Stafford. The two lived through the many waves of consolidation in New York investment banking: in 1986 they went to work for Shearson, which became Smith Barney, which became Morgan Stanley. Today they are wealth managers calling themselves "the Lily Group," under the Morgan Stanley umbrella.

Because an early client was the pension fund of a labor union, the Lilies were tasked with some investment screening. The union asked them to avoid investing in companies known for union busting, to refrain from directly or indirectly investing in South Africa during Apartheid, and not to buy bonds funding a nuclear power plant. A few years later, they were adding companies supportive of gay rights to their clients' portfolios. "Our socially responsible investing began with the practice of screening for companies people didn't want to work with," says Engelhardt. It has evolved with the market, and today includes proactive impact investing, and shareholder activism through proxy voting to influence corporate practices.

In 1992 the Lilies began investing in a green fund, in response to client demand, and soon after they helped convert a Morgan Stanley value fund into a socially responsible fund. At this stage, still working with unions, they noticed that a large group of women was behind a garment industry pension fund interested in socially responsible investing. When they held a workshop to educate workers, mostly women, "we were stunned by how little they knew," recounts Stafford. "They didn't know what questions to ask. They needed to be empowered."

This drove the Lilies to reach out to women as clients. "Even today, when a brother and sister come in asking us to manage, the sister will tend to defer to the brother," says Engelhardt.

Indeed, a recent study by the Spectrem Group showed that although the number of wealthy women in the US is growing at a much faster rate than that of men, more wealthy women consider themselves "only fairly knowledgeable with a great deal to learn."

So with women clients the Lilies make an extra effort to educate and empower. The Lily Group web page promises women a holistic, sisterly approach with plenty of personal attention. "Your money is probably just as intimate as your marriage," says Stafford. "It's a very guarded topic. And women have always taken care of women."

The Lilies take calls at night from clients who have waited to tuck in the kids, and offer crayons in the office. They enjoy hearing women outline their dreams and goals and chat about the obstacles in their way.

Over the years, women have been warmed by the Lilies' welcoming approach, and also drawn to their emphasis on sustainable investing. "We've found in general women are more attuned to gun control--they'll say no defense, no gambling, no alcohol in my portfolio," says Engelhardt. "They care about domestic partnerships, they care about women in the workplace, they care about privacy issues, social justice; child labor is huge. Another thing that concerns women is animal testing in the cosmetic industry. And cleaner energy is a big focus, especially now that the Rockefeller Foundation is divesting from fossil fuels."

The Spectrem study confirms women's inclination towards sustainability: 86% of high income women consider the reputation of companies they are investing in, and 46% specifically consider the social responsibility of companies. These numbers are much higher than those for other affluent investors.

The Lilies won't turn away clients not interested in socially responsible investing, but they'll offer them lots of options. And there are many options available today that are socially responsible and profitable at the same time. Indeed, there are studies to show that companies with more female directors outperform companies without women on their boards, and that companies highly ranked for sustainability perform better than general stock indexes.

The Lilies are not alone on Wall Street, or elsewhere in the financial industry, though we don't hear much about these quiet changemakers. There are both a growing number of women in finance, and more investment managers who are socially responsible, women and men alike. Maybe it's time to look to their kind to take the lead.