Researchers working in the fields of family studies and psychology show motherchild relationship dynamics affect the occurrence of childhood overweight and obesity. Many of the significant behaviors they identify relate to negotiation and generosity norms in the household. The primary objective of this study is to test the value of altruistic and collective models of household behavior using the dictator and ‘carrotstick’ laboratory experiments. We also test exploratory hypotheses relating mother’s generosity and child’s punitive behavior and mother-child weight and fitness outcomes using dictator and ‘carrot-stick’ games. The data were collected from 50 mother-child pairs in Laramie, Wyoming. The children were all eight to 10 years old. The mother’s completed a survey to measure family attitudes and beliefs around food and fitness. All of the mothers and children completed a fitness assessment and blood draw to measure their cholesterol, triglyceride, and hemoglobin levels in addition to the economic experiments. The data do not support altruistic models of familial utility maximization as suggested by Becker’s Rotten Kid Theorem. We do find children overwhelmingly influence mothers’ allocations to maximize child, not household, welfare or utility. Results also indicate there is a positive relationship between mother generosity for child junk food the child’s waist circumference. Children who demand punitive behavior in the ‘carrot-stick’ game were less fit and more likely to be overweight and obese. The results of this study offer insights into household allocation processes which effect both mother and child weight and health outcomes.