We are booked on a flight tomorrow to LAS through MEM on an evening flight. A flight earlier in the week was 2 1/2 hours late getting in to MEM for the connecting flight to LAS. Which it missed. There are no more DL or NW flights that night. I did see an AA and a UA flight around that time, but both planes were sold out of coach seats. They both had 1st class available. What happens in this scenario. Sorry to all that my problem description was not informative enough. We are departing from CVG. Because of family issues we have less than four days in Vegas. If I have to overnight I would rather go back to CVG Monday morning. Would Delta allow that if the problem were to be within their realm of control? Thanks