This is common and can be caused by dry air, weather changes, post-nasal drip, or acid reflux. An elevated pillow, a humidifier running through the night, Vitamin D drops, and an extra layer of clothing can all help. If caused by acid reflux, avoiding certain foods and waiting 2-3 hours after dinner before sleeping makes a significant difference. If the cough persists beyond 2 weeks, consult your paediatrician — nebulisation may be recommended. Some parents report it resolving on its own within 2 weeks without intervention.