Why do babies develop fears?

1. A baby’s fears

Upon entering this world, a baby is filled with curiosity. They explore by touching and looking at everything around them, often appearing highly excited.

However, if parents are too busy and bring in a caregiver (such as a nanny) to look after the child, the baby may show strong resistance—reacting intensely even when a stranger simply gets too close. Generally, babies prefer to keep at least one of their parents within their line of sight; if a parent moves out of view, the baby is likely to become quite distressed.

2. When do these fears emerge?

Between the ages of 7 and 9 months, children begin to develop a sense of fear, particularly when encountering unfamiliar things. They often show signs of fear when faced with strangers—for instance, if a nanny or a relative they have never met before appears, the child might scream or cry. This type of fear is known as "stranger anxiety."

Furthermore, if you leave your child in someone else’s care for a while, they may become deeply afraid of your departure—even if the person looking after them is someone they know well.

3. Why do babies develop fears?

What causes children aged 7 to 9 months to experience fear? Some research suggests that this fear arises because the child has learned to distinguish between things they know—or are familiar with—and things they do not.

As a child’s knowledge of the world expands, their fear of the unfamiliar tends to grow as well. In essence, the cause is quite simple: fear emerges the moment a child learns to differentiate between the familiar and the unfamiliar.

Some view fear as a "biological mechanism"—an instinctive human response to the unknown—since unfamiliar things may inherently carry potential threats. Therefore, this is a perfectly normal part of the developmental process.