a french woman named sophie meneut who lived across the river in manhattan. >> was this divorce because of the other woman? >> no, it definitely wasn't because of the other woman. they had been talking about divorce before, uh, sophie. >> reporter: the detectives had a lot of questions for the women in rob's life. >> coming up -- the estranged wife. >> we did bring her in and speak to her. >> and the new love. >> she was crying. she was shocked. >> police wondered did either have a motive for murder? when "dateline" continues. hey, l'eggo my eggo. uh uh. not c-c-c - cause i have the and i - i. that's a lot. raisins. really? what just happened here? you know the rules. i make the rules. know the rules. keep your eggo. l'eggo my eggo. i'm doing this for you, dad. thanks son. hundreds of dollars on youmy car insurance. saved me huh. i should take a closer look at geico... (dog panting) geico has a 97% customer satisfaction rating! and fast and friendly claims service. speaking of service? oooo, just out. it was in. out. in! out. in! what about now? that was our only shuttlecock. take a clo