Sunday night I sang rock-a-bye under the watchful eye of Ralph Sampson.

Sometime over the weekend -- I don't remember exactly when, because at the time I didn't think it made any difference -- my 6-year-old came bounding into the kitchen announcing that his brother the 16-year-old needed a knife.

I was at the sink, and not about to dry my hands in order to arm my sons with a knife. "What for?"

"For something he's doing." I could tell this line of inquiry wasn't going to go far, but since he was after a table knife I decided not to press the issue. There are only so many prying questions a mother can get away with; from a strategic point of view, it is important to save those for episodes that appear to involve gushing blood or moral turpitude rather than use them up on behavior that is merely bizarre. Soon he left, and I returned to the dishes.

Not long after that, I heard strange noises coming from the 6-year-old's room. The door was closed. No mother worth her salt is going to ignore that. I went upstairs and at the landing heard the 6-year-old saying, "and this one, too. Take this one down, too."

It should be noted here that for better or worse I am chairman of the Fine Arts Committee of our household. This came about because I am married to a compulsive hanger-upper who thinks there is nothing more beautiful to hang on the wall than the latest artistic effort of a child. This is fine if you don't care what your living room looks like; if, however, you are somebody who has spent some time deciding what color you want on your walls and what pictures you want hanging where, then the chances are that you will not select the latest work from your preschool child as the perfect finishing touch. A compromise of sorts was struck some years ago when it became clear that my husband had spawned a new generation of compulsive hanger-uppers.

Henceforth, all art work done in school that was not immediately bid upon by the Louvre would be hung in the artist's quarters or, if it was especially good, in the family room. Exceptions were made for seasonally adjusted art; thus, a large paper turkey might appear on the mantelpiece but disappear promptly after Thanksgiving, into a box.

Each child was named curator of his own room and could hang up just about anything that was within the bounds of good taste. Good taste, of course, has to remain flexible. Posters of "Kiss" barely got the good taste stamp of approval when they went up in my oldest son's room five years ago. Now, after punk rock and people sticking safety pins in their cheeks, no one would bat an eye at "Kiss." It was, however, with some relief that I saw them come down and Susan Anton go up. As the exhibitor changed, so did the exhibit.

By the time I got into the room to explore what was going on, most of the 6-year-old's early works were on the floor. While he bounded from bed to chair to floor, supervising the operation, the 16-year-old, knife in hand, was going from wall to wall, from sketch to painting to handcraft, taking out thumbtacks, dismantling his brother's past.

"Why are you taking that down," I asked in horror as a paper plate decorated to be a scary mask hit the carpet.

"That's baby stuff," said the 6-year-old. "I'm way too old for it."

"But you made that," I protested. "It's very nice."

"Mom," said the 16-year-old, pointedly. "He wants to take it down."

"And this," I said, stooping to the floor and picking up a paper covered with orange and green crayon marks. "This was one of your earliest drawings!"

"That's scribble-scrabble," came the response. "I don't want that on my wall anymore. I'm too old." Sunday night, tucked in bed, the 6-year-old requested a lullabye, as he has done every night for years. He made room on the side of his bed. Above his headboard where there once was scribble-scrabble was a huge poster of Ralph Sampson, a gift from his brother.

"I like your room," I said at the end of the lullabye.

"It's a boy's room," he said softly. "A big boy's room."

And I wondered how many more lullabyes there would be.