Don’t assume the older children are behind every argument.  After some private detective work I saw firsthand that my young one had quickly learned to push all the older kid’s buttons.  She just wanted attention, and negative attention from either her parents or her siblings, is still attention.  As a parent, our greatest disciplinary tool is listening so that we can then, in turn, make the correct judgments.  Rather than get caught up in the chaos of the day, I made myself slow down, listen first, then respond to each problem individually rather than automatically assume that the older kids were the cause of the disagreements.

 Teach all the kids about personal boundaries--again.  I spent a lot of time on this when the older kids were younger but seemed to forget about it when the baby was born.  When a new child is added, you start all over again.  Special attention needs to be taken with younger siblings so that they understand they can’t touch things that don’t belong to them or go in their brother or sister’s room without permission.  They don’t learn this through osmosis.

Reinforce respect by all family members.  Older children that feel respected by their parents are much less likely to be intolerant of younger siblings.  When mutual respect is cultivated, siblings can become friends even when they are separated by many years.  So, make sure the kids see you doing things like knocking before entering a room, or make it a point to ask your child’s permission to use a special marker.  Set the example.

Older kids are not the parents.   When our youngest was born, my husband and I explained to our older children that if we did have another child, they would be role models.  Their younger sibling would look up to them and mimic their behavior, and because of this, we expected them to take this into consideration when they made choices.   I thought this was a brilliant strategy, but I learned quickly.  When you place the responsibility of being a role model on the shoulders of older siblings, they may interpret that to mean that they are also allowed to discipline their younger sister or brother.  Chances are, a parent would not react the same way to problems that require discipline, as does the older child, and it’s important to help the older child see that being a good role model is different than being a disciplinarian.  The younger child should look to the older for direction, but not discipline.  I will never forget my youngest daughter’s observation one day after spending the afternoon with her oldest sister.  “Mommy, I know she’s seventeen and I’m only seven, but she is my sister, not my mother.”  Excellent point.  Parents must remember to draw clear boundaries so that both older and younger siblings understand their responsibilities to each other. 

Babysitters R Us.
Parents automatically assume the older kids will just love to baby-sit the new baby.  They don't.  As a matter of fact, they resent the implication that it is expected.  If you want to promote positive interaction between your new child and much older siblings, do not merely expect cooperation.  It wasn't their idea to have this child.  It was yours.  Plan ahead so older kids have plenty of time for their own social life.