Being green, varies from person to person. There is no way of being 100% green. Most people who are trying to live that way know that. My guess is a good part of their own clothing is not "green", nor quite a few of their possessions. Get cotton fabric and go for an organic cotton batting and you will be fine. I agree about the bamboo batting, it's pretty processed. Make the lovely baby quilt, do the best you can and I can pretty much guarantee they will love it. :)