I'll start with the last question. In general, for a three-year-old child, entomophobia (fear of various insects) is not an inherent phenomenon. Children under five years of age treat every living creature with great interest, not experiencing disgust or fear, especially if none of the adults instill these feelings.
Therefore, if a young child has fears associated with insects, then most likely it is a phobia provoked by one of the adults.
Either one of the family members has such a phobia and is demonstratively afraid of insects in the presence of a child, or no less defiantly fights insects: “Cockroach! Hit him! Hit him! Fly! Beat her! ”
That which causes such a gambling aggression of an adult is probably very dangerous - a kid can come to such a conclusion, starting to be afraid of these small but such terrible creatures. In our human view, even such cute and beautiful insects like butterflies, upon closer inspection, turn out to be rather unsightly and frightening.
There is one more, unfortunately, quite common way of finding such a phobia: when someone older than a baby, not necessarily an adult, consciously scares a small child: “If you do not collect toys, Tarakanishe will come, steal you and eat you!"It is not surprising that after a couple of repetitions of such phrases, the child will become afraid of cockroaches in panic.
Of course, in dealing with a child you should not deceive, telling him that there are absolutely no insects nearby. If the insect is found out anyway, the hysteria will most likely be lost, and the confidence in the parent who has deceived on such an important issue will be undermined.
It is better to focus the child’s attention on the fact that the parent can protect the baby: “I can protect you.”
You can start with a similar phrase, so that your child becomes calmer under the protection of an adult. He himself does not feel in moments of fear of being able to stand up for himself before a frightening animal to tremble. Confidence in the strength of an adult soothes the child.
Then you can go to phrases like: "When we are together, we will cope with any insect."
In this case, the child, just like an adult, is endowed with strength and confidence to cope with the situation, even if not independently, but in a team with a parent, but this is an opportunity to help him feel differently in the face of possible danger.
This is an intermediate step on the way to: “You will cope - insects are not terrible to you!”
If the child continues to be worried after the soothing words of an adult, you can take his hand and go around the room together to check how things are going with insects, and make sure that nothing threatens. This is not a whim of a child, in fact such an action will help him to find peace.
As a rule, it is natural for a person to be afraid of what he does not understand, or of what he knows little about. Therefore, if we look at an atlas or encyclopedia with a child that is age appropriate, the sections on insects can get a good therapeutic effect. A child gets acquainted with a fly, sees how it works, what it feeds on, how it lives - the fly becomes close and clear, it loses a frightening halo of mystery and uncertainty, the child calms down.
It is good to read fairy tales with a child, where insects are the main good characters. The most famous, of course, is the tale of “The Fly-Tsokotukha”, but besides her, V. Suteev has a number of tales with his wonderful illustrations. Maybe the baby will first simply listen to the fairy tale, not wanting to look at the pictures, or even refuse to listen at all. No problem, you can return to this offer later.
When the child is already without awe listening to the fairy tale about insects, you can offer him a clay from the clay who he liked. It is good if an adult also takes part in modeling, and not just observes. When the clay heroes accumulate a sufficient amount, you can organize the clay theater, in which the child, who is not afraid of them at all, will be the main puppeteer managing the once frightening animals.
A little imagination and creative enthusiasm will help an adult to rid the child of anxieties and fears associated with insects.