Crisis at Cornell. Husband on trial for missing wife's murder. Plus, "The Widower" documentary.

In New York State, tensions escalate on Cornell campus over allegations of sexual assault at the Chi Phi fraternity house in 2024. In Virginia, young nurse and mother Mamta Bhatt went missing two years ago. Her husband is now on trial for her alleged murder. In Ohio, former American Idol contestant Caleb Flynn, convicted of murdering his wife, Ashley, speaks at his sentencing. His daughters' letters to him were read in court. Plus, Dateline Senior Investigative Producer Dan Slepian discusses new Netflix documentary, "The Widower: ‘Til Death Do Us Part."