Last fall when I learned that my 20-month-old daughter Katie needed to have an operation on her leg to remove a large birthmark that could turn malignant, the unhappy hospital memories of another little girl who'd had her appendix removed at age 2 flashed back once again to haunt me. My earliest childhood memories begin in the hospital, alone and hurting.

My husband also had been hospitalized for long stretches as a youngster -- back in the days when there was no such thing as parent participation in a child's hospitalization and hospitals restricted parents to brief and infrequent visits.

Although we both knew intellectually that pediatric medicine had changed for the better, our emotional response was the same. We were determined Katie would have a "different hospital story" from her parents'.

"If a child is properly prepared and given a lot of support before, during and after hospitalization, then the experience, while being stressful, can actually be one that enhances self-esteem," says Sherrie Vavrichek, a Takoma Park clinical social worker who specializes in work with handicapped and chronically ill children and their families.

"For instance, a child who requires surgery who has practiced receiving anesthesia throughout play with the parents can face what would be a frightening experience with a fair amount of confidence. They know what will happen. When they wake up from the surgery, they can feel proud that they were able to master a stressful situation and their trust in their parents who helped them is reinforced.

"Furthermore, parents who are actively involved as resources to their child feel less helpless because they are providing their child with the kind of emotional support that only they can give."

Probably the most stressful part of having your child hospitalized is the sense of helplessness when you must surrender your child to the kindness of strangers. So while I knew that I couldn't control all the aspects of Katie's medical treatment in the hospital, I was comforted in knowing that I could control her preparation beforehand. Very soon, however, what began as an exercise in getting Katie ready for the hospital became a preparatory program for the family.

Several weeks before the operation we gave Katie a new doll named "Maggie" that my sister had made especially for the occasion. Maggie had an identically shaped brown felt birthmark on her right leg just above the ankle and we called Katie's attention to the coincidence.

We also began to introduce hospital stories with children as patients into our daily reading, just as earlier we had begun reading books on doctors. But while most books on a child's hospitalization are good, most are written for older children. So I made up a toddler's tale:

"Once upon a time, there was a little doll named Maggie who needed to go to the hospital to have her birthmark removed from her leg . . ." At this point we did not tell Katie she would be going to the hospital, but used Maggie to gently introduce the concept of hospitalization. Katie particularly enjoyed hearing Maggie's story and we told it many, many times.

As the time grew closer for the operation, we introduced the hospital in play. Because Katie's surgeon, Dr. Kathryn Anderson of Children's Hospital, had earlier warned us that the most difficult part for toddlers was the anesthesia induction, I bought Chicco's "Medical Center" ($17.97, Toys R Us) because it came with an anesthesia mask. We made up a game called "The Doctor Is In" and showed Katie how to administer anesthesia as well as give shots, take blood pressure, etc.

As any parent knows, kids love playing doctor and Kate was no exception. At times the living room, littered with sick dolls, bandaged animals and parental guinea pigs looked like the Civil War hospital scene in "Gone With the Wind." After a few days of our playing patient, Katie was willing to let us place the mask over her face.

She was to be operated on a Tuesday. Each Sunday afternoon Children's Hospital has a pre-admission program called "A Hospital Visit With Clipper" (a hospital tour, puppet show or film and party) for families and children entering the hospital the following week. We told Katie Sunday morning that she and Maggie were going to have an operation soon and then we went off to have a look at a real hospital. By the end of the afternoon, I think the whole family was ready for Katie to go to the hospital.

Katie and Maggie went together to Children's Hospital. Even though she was only going in for short-stay surgery, the night before we ceremoniously packed a small suitcase with some of Katie's favorite things: a family photograph, her blanket, an extra pacifier. I slipped in a miniature hospital gown for Maggie, so that when Katie put hers on, so did her doll.

Everyone at Children's Hospital took having an extra patient in wonderful stride: from the admissions office assistant who made sure "Miss Maggie Mavourneen" had her own identification bracelet to Katie's doctor, who removed the felt birthmark from Maggie's leg in the operating room and bandaged it with similar dressings.

Earlier Dr. Anderson had drawn a picture to show what Katie's scar would look like; the night before the operation I painted a scar on Maggie's leg with flesh toned nail polish, so that when the bandages were removed the two patients would even have similar scars. Katy seemed to benefit from sharing the experience with Maggie and still shows off their matching "badges of courage" to family and friends.

The emotional payoff for all this preparation came at the crucial moment of the anesthesia induction. We were all able to be together. Katie sat on my lap while her father held her hand. When the anesthesiologist held up the mask and asked, "Do you know what this is, Katie?" she nodded and surprised the doctors by reaching over and placing her small face into it, ready for her operation, secure and prepared.