Are you an oldest, a middle, a youngest, or an only child? How did your position help form your personality? There are a number of influences in forming our personalities: gender, genetics, temperament, our parents' parenting style and ability to attach, environmental and socioeconomic factors, and birth order. Birth order can help explain how children in the same family can grow up to be so different. Birth order can also be fun to look at with couples, as it can be predictive of conflicts.

What are oldest children like? Oldest children get things done. They can either be "compliant nurturers" or assertive. They tend to be exacting, precise, and particular. They are often achievement-oriented, capable, and successful. Those same traits that cause them to be successful at work can cause conflict at home.

Because first borns are the pilot project for new parents, who are often excited and anxious to get it right, pretty much every first for an oldest is celebrated and important. First borns model themselves after the adults in the family. They tend to be organized, on time, and in control. They can also feel a lot of pressure to succeed and sometimes become a secondary parent to younger siblings.

As a growth opportunity, first children need to be sure not too be overly critical of themselves or others. They need to be positively assertive, but not bossy (where they alienate others). They often need to loosen up a little and learn to relax. It's important for oldest children to learn to give consideration to the thoughts and feelings of others, and not act as if they are always right. These individuals need to watch out for perfectionism. Cultivating flexibility and avoiding rigidity is essential. Patience is a virtue oldest children need to learn to truly be successful with others.

Imagine the fun and the potential conflicts when two oldest children decide to partner or marry. Can you say power struggle?

Only children can be functionally like super-charged first borns. They can grow up to be highly perfectionistic. It's also important in understanding the only child to know how they became an only child. Did the parents want additional children and couldn't have them? Did parents plan to have just one child? These parental factors influence the way an only child grows up.

Middle children tend to get along well with others. Psychologist and birth order researcher Kevin Leman calls middle children "mysterious." Their personality is formed partially in response to how they perceive their older sibling. Middle children can be very well-adjusted, and be peacemakers and mediators. They often turn towards friends for support, and can be highly independent and mentally strong. Middle children need to be encouraged to open up, express their opinions, feelings, and preferences.

What about the baby of the family? Last born children tend to be personable, outgoing, and a bit charming. They can be affectionate, like the limelight, but can alternatively tend to be rebellious, over indulged or manipulative. Parents may be more relaxed or worn out by the time the youngest arrives. The youngest child needs to learn to be responsible, direct, and consider other peoples needs.

The middle and youngest child are always affected by the oldest child in the family and the shadow they cast on the family. If the oldest is impacted by problems or disabilities, we can see a middle or youngest child becoming the acting or functional oldest. Other losses, such as parents losing a child or having a miscarriage, also play into birth order.

There are studies reported in Kevin Leman's excellent The New Birth Order Book (Revell Publishers, 2001) which suggest some predictable patterns with certain birth order matches. While there are modifying factors, having a different birth order from that of your partner is considered an easier or more natural match. When you have two oldests, they may get into power struggles unless one is more aggressive and one is the pleaser type of oldest. Two youngest children may be wildly irresponsible together, including with finances. An oldest and a youngest is a good match. Middles are so well adjusted they could easily have an oldest or youngest partner. Two middles may not communicate that well with each other.

As parents, we also want to consider both order factors. We want to avoid the natural tendency to overly identify with the child that has our same birth order. We want to help first borns learn to ease up on themselves and others. Oldest children need us as parents to help them move towards excellence, but not perfectionism. We can encourage middles to express themselves and help them not get stepped on by siblings. We can help develop the emotional maturity and responsibility of youngest children. 

Birth order doesn't change when people remarry or blend families. It can, however, predict where conflict could occur and how to help prevent it.

In counseling individuals, couples, and families, I always ask about birth order and siblings; I'm curious about how it figures into your relationships.

Whether you are a typical or atypical person for your birth order, understanding the role birth order usually plays for individuals and relationships can give you valuable information about understanding yourself and others better.