11-year-old singer Jackie Evancho performs at the first annual American Giving Awards, Friday, Dec. 9, 2011, in Los Angeles. The awards show granted two million dollars to five finalist charities. (Chris Pizzello/AP)

The author G.K. Chesterton called the act of stealing a child’s toy the cruelest crime of all. But what if childhood itself is stolen away?

By now, some of you may have run across a certain young soprano named Jackie Evancho. The 11-year old from Pittsburgh, introduced to the public on the television program “America’s Got Talent,” has since gone on to release two full-length albums, which have collectively sold several million units. PBS went so far as to present a filmed “live concert” of her album “Dream With Me” on “Great Performances,” once the domain of Leonard Bernstein, Vladimir Horowitz and the Metropolitan Opera.

According to Evancho’s Web site: “Her first on-air performance, in which she sung Puccini’s ‘O Mio Babbino Caro,’ delighted the judges. . . . ‘I can’t believe that from this tiny body, this huge mature voice you have,’ said Sharon Osbourne. Piers Morgan said, ‘This is one of the most extraordinary performances that I’ve ever seen on ‘America’s Got Talent.’ Howie Mandel simply stated, ‘You’re an angel. You’re a superstar.’ ”

Very well: By certain standards, Evancho may now be a “superstar,” as Andy Warhol would have understood the term. But she has many years of work ahead of her before she becomes any sort of musician — and I fear that this premature and unwarranted exposure will ruin a genuine and valuable talent. A sweet-faced child with a naturally pretty voice is being primed, packaged and promoted as though she were a finished artist. And she isn’t — not yet anyway. Right now she reminds me a lot more of JonBenet Ramsey than she does of Maria Callas.

Just what do we hear when we put on a Jackie Evancho recording? “O Mio Babbino Caro” will do for a start. One is startled immediately by the lush sound that Evancho makes, which would never be expected from somebody her age. But then the worries start. Her interpretation seems little more than imitation — almost ventriloquism — with scarcely a trace of originality. She is comfortable only within a small range. The rest of the time, she is reaching hard for high notes or scooping for low ones. Her phrasing is shaky and unsure; her anxiety is palpable; there is nothing “easy” or free-flowing about her performance. All in all, figuratively speaking, one has the sense that she is trying very hard to fill gigantic shoes that may well fit her someday but could easily wreck the way she walks if she persists in wearing them now.

And this is the problem. At the age of 11, Jackie Evancho should be permitted to sing “like a girl”; instead, by her own design or not, she is singing as a mannered and uncomfortable woman. Why not folk songs and smart pop music and maybe some of the simpler Schubert lieder instead of grand opera? Why not let her sing in a chorus, work with adults who will love her, encourage her, nurture her talent and make her into the finest artist she can be?

Indeed, the cult of the prodigy has always struck me as one of the most debased aspects of the music world. If I were king, I think I would put some kind of ultra-restrictive law on the books that would permit the best and the brightest of our children to flower to ripeness, follow their curiosities, study their art, learn about joy and heartbreak and, ultimately, to turn into people before they are trotted out as the latest phenomenon.

I mistrust the “cute kid” brigade for two principal reasons: It is deeply exploitative and often ruinous to young artists, and it transforms age — which, after all, provides a natural accumulation of musical and personal experience — into a liability for more seasoned players. You’re the hottest thing around at age 11, making millions every year. Where will you be at 21, as you begin to enter full maturity? And who will look at you when you are in your 30s? There will always be somebody younger than you are; adulthood becomes a threat instead of a natural process.

Take the case of Charlotte Church, who was touted by some (never by professional musicians) as the great child singer of 1999. She hit high notes with a fierce, sexless intensity that never failed to wow the general public but that were also forced, unnatural and proved profoundly damaging to her young voice, straining it until it lost both agility and luster.

Or, going back a few years to a much greater artist, look at what happened to the violinist and conductor Yehudi Menuhin. He made his Carnegie Hall debut at the age of 11 playing the Beethoven Violin Concerto. (His anxious, ambitious parents rewarded him by taking him out for as much ice cream as he could eat.) “Now I know there is a God in heaven!” Albert Einstein exclaimed after hearing the boy in 1929. (“Superstar” was not then in the parlance.)

At his best, Menuhin offered playing that was distinguished for its sweetness, purity and spiritual intensity. But he was not always at his best. Indeed, such were Menuhin’s intuitive powers that he played the violin magnificently without knowing exactly what he was doing. In 1928, for example, when he was granted an audience with the Belgian virtuoso and composer Eugene Ysaye, he played the Lalo “Symphonie Espagnole” flawlessly. But when it came time to play a scale, Menuhin later recalled that he “groped all over the fingerboard like a blind mouse.” He fell into many bad habits and, in young adulthood, was forced to rebuild his technical perception of the violin, learning to master consciously what had previously been managed as a sublime freak of nature. It might be argued that he never entirely recovered.

A happier story is that of Hilary Hahn, who was a celebrated violinist by the time she was in her mid-teens. She was always a lovely player — sweet-toned, inquisitive, brimming with ideas and intelligence — but she grew up to radiate a strength, precision and confidence that can come only with maturity, and then only to a very few, meticulously trained musicians.

Singer Charlotte Church. (TOM UHLMAN/AP)

Yo-Yo Ma is another child prodigy who has sustained his artistic integrity from childhood through to middle age. “I hear parents telling their kids that they, too, can be famous soloists if they work hard enough,” he once said. “That, to me, is the worst thing you can do to a child. If you lead them toward music, teach them that it is beautiful, and help them learn, say, ‘Oh, you love music, well, let’s work on this piece together and I’ll show you something,’ then that’s very different. That’s a creative nurturing. But if you just push them to be stars, and tell them they’ll become rich and famous — or, worse, if you try to live through them — that is damaging.”

In no way am I suggesting that Evancho’s parents have indulged in this — how should I know? — but the temptation to create a “star” should be resisted at all costs.

Ma was well known in musical circles by the time he was in his teens, but his stardom came later. He has credited this to his training at Harvard University, which he attended after seven years in the Juilliard preparatory division. “Attending Harvard instead of a conservatory was the single best thing that ever happened to me,” he said. “I started meeting people who were at least as passionate about their fields as I may have been about mine.

“It opened up new worlds,” he continued. “It made me get out of myself and think about music as it related to the world, in a very different way than if I had just concentrated on my scales and exercises. It made me much less neurotic. Performances were no longer the only thing in the world. My whole life didn’t depend on the success or failure of a performance, and I could see that there were other things that I could be if I were not a musician.”

But singers face a greater risk than violinists and cellists. If, by some horrible accident, something happens to Ma’s cello, he can quickly find another one. But if you are a singer and you wreck your instrument, there is nothing to be done — for your instrument is within you. Voices, if they are well trained and intelligently cared for, can last a long time. Placido Domingo is still singing, sometimes brilliantly, in his 70s, after half a century on the operatic stage. And, unless Evancho undergoes some serious training, we will be lucky if she is singing much of anything in a dozen years.

“I sometimes get scared of growing up because I really love being young, being little,” Evancho told NPR last year. “It’s fun. A lot funner than being an adult.” Maybe so, although I certainly didn’t find it that way. Nevertheless, adulthood happens to all of us who are fortunate enough to live that long — and, at a time when Evancho should be building and learning, she is instead squandering her natural treasure.

Page, a former Washington Post critic, is a professor of music and journalism at the University of Southern California and the author, most recently, of “Parallel Play.”