Descriptive statistics of the measured variables.

The family is a crucial contributor to mental health and physical well-being. While bidirectional relationships between physical activity, diet, sleep, and mental well-being are well-documented, the influence of the family on these behaviours is less explored. This study aimed to examine the relationships between family resilience and individual lifestyle behaviours in community-dwelling adults, focusing on the roles of a supportive family health climate and reduced biobehavioural reactivity. Data were collected from 200 family dyads in Singapore through questionnaires assessing family resilience, health climate related to physical activity and nutrition, individual lifestyle behaviours (physical activity, diet, sleep), and demographics. Structural equation modelling was used to explore the connections between family resilience and individual lifestyle behaviours, particularly how family health climate and biobehavioural reactivity mediate these relationships. Participants included 200 dyads with a mean age of 42 years (SD = 15.18; range 15–85), 62.7% female and 67.3% with tertiary education. 85.5% were Chinese households and 83% lived in public housing. Family resilience was associated with increased engagement in physical activity, diet quality, and sleep quality, with higher engagement linked to lower biobehavioural reactivity and a healthier family health climate. Significant mediation effects were observed, with family resilience positively influencing physical activity (total indirect effect: β = .164, p