Editor's note: Jane Isay is the author of "Mom Still Likes You Best: The Unfinished Business Between Siblings," and "Walking on Eggshells: Navigating the Delicate Relationship between Adult Children and Parents."
(CNN) -- Physicists may dream of time travel, but in families it's an everyday occurrence. One look from an older sister, and you're propelled back to the nursery. Watch your brother hog the holiday cookies, and you're a small person all over again, brooding at the dinner table.
Growing up with siblings is one of life's great gifts -- and challenges. The nursery is where we learn to deal with peers; it's where we experience and tame powerful feelings of love and jealousy. We teach each other to fight and to compromise; we learn about loyalty -- and betrayal. Unfairness is our constant companion, as is kindness.
We also learn how to push each other's buttons; in fact brothers and sisters install them in each other.
Those buttons never go away, it seems. One look, one sneer, a tone of voice or tilt of the head, and we're children again. We watch the favorite suck up to Mom or Dad. "There he goes again, I can't stand it," we think. We notice the eyebrow raised at our hair, or weight, and it makes us crazy.
As adults, we understand that children inhale their parents' judgments and pass them along. And observing our own kids, biting and kicking, lying and pinching, we recognize the universality of such behavior.
The truth of the matter is that brothers and sisters can uninstall these buttons, too. We can reframe those experiences and see them in a new light.
A good way to rid ourselves of these buttons is to exchange roles. If you were the "smart" one, listen a little more respectfully to your "pretty" sister. If you were a demanding little kid, offer some help to your more responsible brother or sister.
I know a pair of successful sisters who were deadly competitive and never let down their guard. They were polite, but tense. Then one woman decided it was time to change. So she offered her older sister moral support when she needed it, and she stopped hiding her own vulnerability. This mutual relaxation was the first step toward reconciliation.
If the events that epitomize your sibling relationships happened in the nursery, look at them again from an adult vantage point. If you are still bruised about the door slammed in your face, about the mean jingle your brother used to sing, remember that you just might have been a bratty little sister.
Small changes in our attitude and behavior may improve our brothers and sisters as well. It's a good idea to leave time travel to the physicists and begin to see the people with whom we shared our childhood as the grown ups they are.