It takes time, generally 3-4 months (longer for premature babies), for babies to start producing melatonin and as a result develop a more "mature" circadian rhythm.
Natural light can influence the production of melatonin as can certain foods such as: tomatoes, walnuts, olives, rice, barley, strawberries, cherries, and cow’s milk, which all contain melatonin.
If you have a baby, toddler or preschool aged child who is not sleeping well, please do not hesitate to reach out to me directly at: email@example.com to schedule a complementary 15 minute introductory phone call to learn how I can help your family get the gift of sleep.
Yours in sleep,
Tracie / Rest Well Baby