Octavia Allis, LCSW has been a clinical and consulting social worker for over 25 years. She is founder of the Renaissance Projects.

Karen was 35 and had not seen her family in five years. Michael was recently diagnosed with Attention Deficit Disorder and was disruptive in class. Sari was the middle child in a household of achievers. Her sophisticated and socially adept parents worried that their beautiful 12 year old was losing weight and self-confidence. They could not understand why she wanted to die.

These people had one thing in common.,they were all verbally, physically, or sexually abused by their siblings.

Most of us grow up in families with one or more children. Most of us have lived through our share of teasing. But some children are regularly ridiculed, shoved, hit, or sexually abused. Experts report that sibling abuse occurs twice as often as parental abuse.

Some psychologists believe that health sibling rivalry gives children the opportunity to learn how to deal with envy and jealousy and is helpful in handling competition later on in life. Most experts believe that unhealthy sibling rivalry can have a lifelong negative impact.

Sibling temperament, sex, birth order, an individual compatability with parents are all factors in the way sibllings relate. The most important factor is their parent's relationship to them and to one another.

Sibling abuse occurs both in famililes where there is parental abuse and in families where there is no recorded parental violence. However, most studies indicate that sibling abuse occurs in families where there is high stress, difficulty communicating, or poor problem-solving skills.

Children who feel powerless or neglected will compete for their parent's attention and may turn their anger and unmet needs on their siblings.

Patterns of behaviors are typically passed down from one generation to the next. Parents who grew up  with teasing and taunting will often dismiss thier children's concerns by saying, "That's just sibling rivalry,"  "They'll toughen up," or "It will help them deal with competition later on in life."

Sibling abuse is often a hidden factor behind the rising rates of obesity, anorexia, and depression.

Sibling abuse occurs with both boys and girls, but boys are more likely to physically or sexually act out. Many experts state that the pervasive cultural nom of male prerogative and permission for males to be sexually, verbally, and physically aggressive is a major factor int sibling sexual abuse. In fact, one recent study indicates that it is common for adult males ro forget or minimize their abuse of their sisters, while their sisters remember in detail and suffer well into their adult years. But occasionally, incest between sibling is the result of unhappy children with umet needs who turn toward each other for comfort.

Young males who abuse sexually aften point to the influence of violent sexual images on the Internet and in the media and may use drugs and alcohol. Girls who have been victimized may often dress seductively and act out sexually.

Though mutual sexual exploration between siblings is common in early years, any forced sexuality including penetration, fondling, forced undressing, exposure to pornographic material, or verbal comments is abusive.

For example, one teen's brothers regularly commented on her developing body. She became so self-consious that she was unable to wear shorts of a swimsuit. She was a natural athlete, but could not bring herself to participate in school sports. Although she was not raped by her brothers she was systematically verbally abused and objectified.

When does normal or health sibling rivalry become abusive? What are the signs? How do we know when to intervene?

Look for persistent patterns of ridicule, putdowns, bullying, shoving, pushing, or intimidation. Is behavoir age-appropriate? Is one child more perfect, withdrawn, passive or provocative that the others? Does your son or daughter seem depressed or angry? Does your daughter dress or act seductively? What about family exposure to drug, alcohol, excessive Internet use, pornography and TV, music, or video violence? Do you have fun together? Do you devote enough time and attention to your children? Do you have a preference for one child? Are you happy, or stressed and overwhelmed? Are you undergoing a lot of life changes? Do you yell, use sarcasm, or physically discipline? Is it easy for you to listen? Do you feel appreciated and heard? Do your children?

When any child in a family feels intimidated or pressured, something is wrong. Take steps to support and protect each of your children.