volunteered to help. >> pattie wasn't allowed to touch the two girls'murder files but she could help in other ways. >> and we just hit it off. she was so supportive, and so positive. and just volunteered for anything she could do to help us, make our jobs easier. >> round then, detective wade decided to try something new. with the crime-scene dna. she consulted this woman. dr. colleen fitzpatrick. an expert in something called forensic genealogy. >> an informal sense, it's been referred as csi meets roots. >> maybe you have taken a home-dna test. a lot of people have. you can sometimes track down distant relatives by uploading your dna profile to public genealogy websites. dr. fitzpatrick searches all that dna data, to find, not