Whay if my child have a lot of small bumps on their body?

Could be Eczema. If the "small bumps" are the same color or slightly lighter as your child's skin and a little dry, then it could be eczema. Pilaris eczema (keratosis pilaris) is a common and benign form of eczema. Though like all forms of eczema, some kids get it worse than others. Consult with your primary care provider or a dermatologist to confirm the diagnosis and get treatment advice.