During these months, a child can sometimes seem like two entirely different people: outgoing, enthusiastic, and extroverted in your presence, but tense, clingy, and easily frightened around unfamiliar people or objects. Some might tell you that your child is timid or shy because you've "spoiled" them, but don't believe this notion. Their contrasting behaviors are not a result of you or your parenting style but rather because this is their first time distinguishing between familiar and unfamiliar. Their predictable anxiety at this stage is proof of a healthy relationship between you and your child.
Experiencing "stranger anxiety" should be one of the initial milestones in a child's emotional development process. You might wonder why your child could calmly interact with strangers at 3 months old but now becomes anxious when approached by unfamiliar people? In reality, this behavior is normal at this stage, and there's no need to worry. Even relatives or caregivers who were once familiar to the child and used to look after them may now cause them to want to hide or cry, especially when they approach suddenly.
Around the same time, they'll also become more dependent on you, which manifests as separation anxiety. They begin to realize that objects are unique and everlasting, but there's only one of you. When you're out of sight, they know you're not with them, which can make them extremely uneasy. Their sense of time is poor, so they don't know when you'll return or if you'll return at all. As they grow older, memories of being with you will comfort them, knowing that they will reunite with you. But for now, they can only comprehend the present moment, so as soon as you leave their sight, even if you're just going to the next room, they may cry out in panic. If you leave them in the care of others, they may cry bitterly, although they usually stop crying shortly after you leave. When sleeping, they may be reluctant to part from you and may even wake up in the middle of the night searching for your presence.