Heat rash in babies, also known as prickly heat, is quite common, especially in warm weather. It's usually caused by blocked sweat glands and can appear as tiny red bumps on the skin. Keeping your baby's skin cool and dry often helps. Dressing your baby in lightweight, breathable clothing and keeping their environment comfortably cool can prevent it. Have you noticed any particular areas where the rash appears more frequently? How has your baby been reacting to it?