Most insect bites allow for injection of venom or other digestive juices into the skin of the child.
The swelling from the bite is not caused so much by these juices themselves, but by the body's reaction to the juices. Some insects, such as fire ants, cause painful bites. Uncommonly, fire ants can cause life-threatening allergic reactions. Most people experience pain and swelling at the site. The swelling may evolve into small fluid filled pustules that itch.