If your 3-year-old daughter is having trouble sleeping, there are several steps you can take before considering giving her melatonin. It's important to establish a consistent bedtime routine, such as avoiding screens before bed and keeping the bedroom strictly for sleep. Make sure there are no stimulating objects in her room, such as electronics or bright lights. Encourage outdoor time during the day to help regulate her sleep-wake cycle. Additionally, you can consult resources for specific age groups to get more tips on promoting healthy sleep habits.