Pre nups are critical for older couples that have children from previous marriages. Each person gets to keep and pass along what they had when they married, again, later in life. Otherwise, one of the partner's children could lose out when the 1st partner dies and the living partner gives everything to their kids, only.
this has happened two or three times to individuals close to me in the past couple of years. I have a pre-nup and my DW likes it because if defines what kids get, what she gets and this will avoid fights if I'm the 1st to pass. It's important that everyone realize that pre-nups just don't anticipate divorce, rather they define asset distriution in the event of death as well. And, as life situation changes, pre-nups can be updated as well. I am very, very, glad that we have one.......and, I have a great wife, great life and absolutely no intention of using it in a divorce.