thing -- cathy was still alive when she was placed in the trunk of the car. so, if javier put her there, he could be charged with murder. why not grab javier up that day and say, "okay, your dna and fingerprints were at the scene. we didn't know that until just now. you're going away for murder unless you start talking"? >> well, let's say that we did that and we bring him in and he says, well, yes, my fingerprint was there because i helped her push her car out of the street a week before. or when i was helping her change a tire. i cut my finger and i bled on it. >> reporter: so instead of approaching javier, daron wyatt spent nearly five months carefully watching him and sam. he learned the two cousins were unusually close. >> sam lived in a one-bedroom little bungalow with his wife and his baby at the time, yet javier was there all the time, sleeping in the same -- essentially the same room. >> reporter: eventually, daron wyatt felt he had enough new information to get a search warrant.