27-year-old son and his girlfriend. cnn sara is with me following the story. incredibly disturbing. no good leads and then text messages became a key part. >> right for months they didn't know what happened. they thought they were running away from financial problems but they were always suspicious of the son because of several text messages they found on his phone to his girlfriend who has been arrested saying these like we need to figure out the best way to take them down, whether it is get some money out of them somehow. then it would solve every single problem and give us a wealthy and amazing life. this case kind of stalled for several weeks until thursday remains were found near this vacant home and they are identified as jeffrey and jeannette navin. they were able to make an arrest. in this case, this was the break. on the day jeffrey navin and his wife were last seen in august