A wet cough lasting over four weeks is considered a chronic cough and requires a detailed pediatric evaluation. Using multiple overlapping cough syrups (which combine mucus thinners and suppressants) alongside oral steroids is generally not recommended without strict supervision, as they can conflict and mask the underlying cause. Please consult his pediatrician promptly to investigate conditions like childhood asthma, allergies, or a persistent airway infection. For immediate comfort, focus on simple home care: keep him well-hydrated with warm fluids, use a cool-mist humidifier, and avoid self-medicating. Do not worry; chronic coughs are very common in children and highly manageable once the exact cause is diagnosed.