Use clothing and blankets rather than fossil fuels to keep warm. Set the thermostat even cooler at night. Heat and cool only those rooms that are used. Families Once in Sierra magazine, a letter to the editor claimed that Al Gore was not an environmentalist, because there is no such thing as an environmentalist with four children. If you are interested in learning more about how to control family size and what some of the benefits are, contact Planned Parenthood Federation of America.
Adoption is another alternative to consider.
In North America, our habits have harmed the landscape in a variety of ways. We seem to have gotten the idea of perfect lawns from the English manor houses, and it does not make much ecological sense. Grass is both an invader species and a monoculture. I worked for a couple of years as a landscaper in Baltimore, and most of my energy was spent trying to maintain plants that were out of place. In addition to the expensive consumption of resources, the grass monocrop simplifies the environment, and reduces forage and habitat for animal species.