a shock, of course. but one of two shocks for sandra. and to those around her, the second seemed somehow worse. her beloved son, tom, up and moved to arizona. >> and she was flipping out about it. >> yeah. >> just -- she had to go there. >> reporter: she demanded jack move to arizona too. >> that woman was off her rocker. her tone was just scary. it was like somebody else's voice coming out of her. >> reporter: but surely that wasn't motive enough for murder? and with plenty of suspicion but little else to go on, wyatt spent months poring over sandra and jack's phone records, bank statements, credit card bills, searching to -- well, he didn't know exactly what he was searching for. but he was getting basically nowhere. >> we couldn't establish a pattern that was suspicious. >> reporter: then as wyatt's investigation sputtered, sandra left.