The Other Woman.

After the divorce from Michael, Tessa raises her daughters Kate and Lara alone. None of them can stand Michael's new young wife Carolyn, a model. But when Tessa learns that she's suffering from cancer and soon will die, she tries to get her kids to accept Carolyn as new mother. She takes them on a trip across the country to her father Jacob's ranch in Wyoming. During this trip, Tessa tries to teach Carolyn about the responsibilities involved in raising kids.