Roughhousing with kids is good. How do I know? Smart guys say so in a book.

Lawrence Cohen, a Boston psychologist, and Anthony DeBenedet, a gastroenterologist from Ann Arbor, Mich. , wrote "The Art of Roughhousing," which includes diagrams and everything. Why you'd need diagrams for playing with children, I don't know, but there you are.

The authors tell us that roughhousing is "rowdy, but not dangerous." One great concept the guys impart is that when we roughhouse with our kids, we model for them how someone bigger and stronger holds back, which teaches self-control, fairness, and empathy.

When my daughter roughhouses with me, I model someone who is frightened of her growing strength. Girlfriend can punch. And kick.

Before the Little Girl was adopted, I read all manner of baby books, which tell expectant parents how to protect the child. What those books don't say is how parents should protect themselves from the kid.

Five of her mild colds blossomed to pneumonia in me. Twice, I was hospitalized. As a baby, she nearly ripped my cornea. She also has injured me a lot in my sensitive daddy place and once slammed my Adam's apple so hard with her head that I fell over making gurgling noises.

My daughter continues to knock me around, explaining that it's fun to hurt me. It's something I'll be sure to bring up at the next meeting of the Battered Dads support group.