First, studies show that there is a bioevolutionary cause that automatically favors genetic offspring. This point is exemplified in the film on numerous occasions. In the film's opening scene, Trent asks Duncan to rate himself on a scale of 1 to 10. Hesitantly, Duncan rates himself a 6, when Trent interrupts, telling him it's a 3 and explaining why. Later, during an outing, Trent embarrasses Duncan by making sure he wears a life jacket on a large boat where he will be the only one. Another example is a point where he emphasizes embarrassing Duncan by asking about a dent in the car in front of everyone. At no point in the film, did we see Trent mistreat his biological daughter the way he treated Duncan. Additionally, studies have found that children in stepfamilies do less well in school, experience more family conflict, endure behavioral problems, and are overall less well-adjusted than children married to a first-time parent. As a 14-year-old, it is normal for Duncan to have difficulty adjusting to his new stepfamilies as younger children generally do better than teenagers at adjusting to their parents' new marriage (Riedman et al.