Erik Erikson, renowned psychoanalyst, theorized that personality develops from infancy into adulthood. Infants imitate their caregivers' facial expressions and voices. This translates into infants developing personality traits that are similar to people with whom they spend the most time. AskDrSears.com says that answering the cry of an infant aids in trust development, while ignoring a baby's cry can alter his personality. Birth order is another factor in infant personality development.
Pick Up a Crying Infant
According to AskDrSears.com, infants cry in the beginning months of their lives as a reflex. An infant senses a need within himself and cries to communicate that need. As parents meet those needs, babies then develop a sense of trust in their parents. AskDrSears.com adds that these babies develop stronger independence and trust in people. Meanwhile, babies who are left to cry are said to develop a sense of mistrust and become withdrawn.
Infants Imitate Personality Traits
A Zero to Three article titled, "The Psychologist in the Baby," by Ross Thompson, explains that as babies reach 2 to 3 months old, they are awake longer to afford more time for one-on-one contact. It is through face time that infants develop certain personality traits. They mimic smiles and laughs. Conversely, if they are surrounded by unhappiness, they will mimic frowning and other sad traits, as well.
Traits That Are Inherent
In the publication "Personality Development: Continuity and Change Over the Life Course," for National Louis University, Dr. Brad Olsen addresses personality traits inherent in nature. He explains that traits relating to disposition are inherent. Calm and relaxed people are born predisposed to that personality trait. It is the same for those who have anxious or hyper personalities. He says what happens in life adds layers to the already present traits that can be seen in the first stages of infancy.
Birth Order Effects Personality
Dr. Jerome Kagan writes in his article, "The Role of Parents in Children's Psychological Development," that birth order effects personality traits. He says first-born children are more likely to become valedictorians of their high school classes. First-born children receive more one-on-one attention than their siblings receive in infancy. This effects their personality development from infancy onward. He adds that first-born children may be more driven and outgoing. Subsequent children may be more relaxed and laid back.