When Erin Aldrich leaves for her Peace Corps assignment in February, she will, in a sense, be living a dream her mother Margie once had."Both my parents have been really supportive," she said. "It's something my mom thought about doing too when she got out of college, but she got married and had me and my sister."Aldrich will spend the next two years in Romania working as an Environmental Youth Advisor."I don't know exactly what I'm going to be doing yet, but it's working with schools, local groups to raise awareness of environmental issues," she said.Now 26, the 1999 Carson …