The “Our Family Vacation” series shows how several American families travel on a budget. Family members: Lissa Poirot: Editor/writer Matt Cooper: High school teacher Zach Cooper, 18 Ainsley Cooper, 17 Braeden Cooper, 13 Sophie Poirot, 12 Ethan Poirot, 11 Hometown: Lehigh Valley, Pennsylvania Annual household income: $180,000 Destination: Washington, D.C.