Recent research suggests a majority of Hong Kong's toddlers (aged 2 to 4) are much less active than is recommended and are increasingly engaged in sedentary behaviour, which places them at risk of becoming overweight or obese. The proposed project will test whether connecting families to nature positively influences physical activity (that is, active playtime) and healthy eating routines in children aged 2 to 4. The investigators have recently conducted a pilot study Play & Grow (P&G), a programme based on the most successful international preschool interventions described in the literature. In addition to adopting healthy eating and physical activity intervention elements, the programme was enhanced by including a novel third element: connectedness to nature (CN). To test the effectiveness of this enhanced intervention, the plan is to run a family-based randomised controlled trial (RCT). The intervention will include 240 families with children aged 2 to 4, will take the form of one-hour activity sessions for parents and children held once a week for 10 weeks. The investigators will assess lifestyle-related habits before, immediately after the completion the intervention, at 6 months and one year after the intervention. Created for this purpose, a novel measuring tool for connectedness to nature, Nature Relatedness Scale (NRS), will be validated and tested for reliability prior to the RTC. The results of RCT are intended to be used to understand which components of the intervention were most effective. The objectives of this project will be achieved over a 36-month period, and it is expected to contribute to a close examination of key components of successful healthy lifestyle promotion programme during early childhood. The investigators predict that is that the new element CN will significantly improve the intervention. Finally, the overall aim is that connecting families to nature will result in sustainable lifestyle changes that remain with them for a lifetime.