her stepdad lives at windyville.as years ago." >> another family suicide? an affair? just where was this investigation going? >>> coming up -- a determined detective. >> he looked at me and told me straight up, "i've never been wrong." >> and a confused friend. >> what did you think? >> i thought they made one of the worst mistakes i had ever heard of. >> when "dateline" continues. moving is a handful. no kidding! fortunately, xfinity makes moving easy. easy? -easy? switch your xfinity services to your new address online in about a minute. that was easy. i know, right? and even save with special offers just for movers. really? yep! so while you handle that, you can keep your internet and all those shows you love, and save money while you're at it with special offers just for movers at xfinity.com/moving. >>> hello. i'm dara brown. here's what's happening. u.n. clip mat summit in glasgow extended past its time as diplomats and negotiators from nearly 200 nations struggled to agree on a deal for reducing emissions and