The aims of the study were (a) to examine the associations between the daily physical activity (PA) of 8- to 9-year-old children and their parents, and (b) to examine what effect the child's daily PA has on its cardiorespiratory fitness (CRF), body mass index (BMI), and health-related quality of life (HRQoL). The sample consisted of 1021 persons [351 children (8.73 ± 0.69 years in age) and 670 parents]. Pedometers were used to evaluate PA in parents and their children over the course of 4 days (Thursday-Sunday), with the instructions on how to wear the pedometers for 24 h a day. Also evaluated were height, weight, BMI, CRF (via the maximal multistage 20-m shuttle run test), and HRQoL (via the EQ-5D-Y questionnaire). Associations between these variables were studied using path model techniques. The father's PA predicts his child's daily PA. This in turn predicts the child's lower BMI, CRF, and perceived quality of life. The findings suggest that the role model of a physically active father positively influences the child's PA habits, and hence that the family environment can have an important part to play in promoting health.