Augmenting incentives for juveniles with separate incentives for parents could boost juvenile efforts to reduce BMI. However, financing a parent incentive by reducing the incentives offered to adolescents could attenuate the juvenile response. In a field experiment, Medicaid-covered juveniles enrolled in a cardiac wellness program were randomly assigned to two groups: juveniles in the focused-incentive group received all earned points; juveniles in the split-incentive group split earned points with a parent. The focused-incentive group was 12.8 percentage points more likely to achieve their stipulated goals compared to the split-incentive group at the end of the 3-month active phase of the program. In contrast, members of the split-incentive group outperformed their peers in the focused-incentive group during the second quarter, and the two incentives structures were equally effective at the year-end session. Additional quasi-experimental data indicates that members of both incentivized groups significantly outperformed (focused-incentive group by 8.48 percentage points and split-incentive group by 11.0 percentage points) a pre-experiment (non-incentivized) set of juveniles enrolled in the same program at year-end.