18 month old rocking

I have a beautiful 18 month old girl who is speaking in 3-word phrases, pretending, pointing to share interests, and very interactive. If I did not have a 5 year old boy with Asperger's Syndrome I would probably not even notice this behavior. She seems to enjoy rocking herself while sitting on the couch. She actually bounces herself off the back of the it and laughs with delight. It looks very much like some of the self-stimulatory behavior my son used to do. Her development appears perfect in every other way. Should I be concerned about this?

[Kevin Kennedy, Ph.D.]

Dear Carla,

It's understandable that you'll be sensitive to the rocking behavior, since your son displays a form of Pervasive Developmental Disorder. However, in your daughter's situation, it doesn't appear you should be alarmed. She seems to be developing well. With the family history, you want to be watchful, but this one behavior alone is not a reason to be alarmed.

[J. Davis]

I am not a professional by any means, but this is something I have always done as a child myself. I would rock my crib across the room according to my mom & dad. In my later years I would do the same thing while sitting on the couch. I grew out of this on my own. But when I am stressed I rock myself to sleep.It soothes me like it did when I was a child. Iam 41 years old and I have an
excellent job. I have a very happy marriage.  Both my parents and
my husband consider me a well rounded and outgoing person.