Welcome to HealthcareMagic. Redness
of the tip of penis in infants can be due to dermatitis
skin. Wear cotton nappies instead of diapers and air dry the area after washing with water when he urinates. Avoid using bubble baths, soap, highly chlorinated water and harsh laundry powders and give plenty of water and fluids to your child. If it gets red, swollen and itchy then it means an infection for which he needs antimicrobials.
Hope it helps. Regards.