Why do infants and toddlers get fevers?

Infection. Infants and toddlers usually get fevers due to their bodies response to an infection (usually viral or bacterial). Substances are secreted by your body when fighting an infection that changes the thermostat in your brain (hypothalamus) to increase the temperature of the body. The fever is helpful for the body to fight infection.
Infection. By far the most common reason for fever in infants and toddlers are infections, with viral infections being the most common type of infection. The infection triggers the immune system to respond with chemicals that effect an area of the brain with controls temperature.
Reaction with germs. Infants' and toddlers' fevers are often from infections. Germs such as viruses and bacteria interact with a child's immune system . . . Resulting in fever. Fevers may also occur from non-infection types of illnesses, but these illnesses are uncommon. A doctor can help decide the cause of a fever.
Infection. A fever, (a temperature of 100.4 or highter) is a sign that your baby's body is fighting an infection. Call your doctor right away if your baby is 8 weeks or younger and has a fever. Sometimes vaccinations can cause mild fever.
To Kill Germs. Fever is your body's way of killing germs. It is a natural and important response to infection. Check out http://www.Youtube.Com/watch?V=q83hamgyc6c and http://www.Youtube.Com/watch?V=zkoevqtnkis.
Immune response. Fever is a response to infection. My simplistic explanation is that the immune system raises the thermostat to cook the germ out of the body.Many times the infection (viral or bacterial) will burn itself out after a few days. The immune system is pretty amazing. If the fever persists or continues to rise, see a pediatrician to make sure infection has not progressed to needing intervention.