Consider three-year-old Shirley Temple, being enjoined by her mother: "Sparkle, Shirley. Sparkle!" She needed no encouragement, and has been sparkling - first in mock naval uniform, latterly in the real uniform of a US ambassador - since. Or Margaret O'Brien, Adle in the 1943 Jane Eyre, and at four-years-old famed for the most precocious professional question of all time: "When I cry, do you want the tears to run all the way down, or shall I stop them half way?"
Judy Garland started her stage career at three, while her co-star Mickey Rooney began working in his parents' vaudeville act when only two.
But it wasn't all roses on the domestic front. Freddie Bartholomew, who starred in the first film of Kidnapped and played the title role in the 1935 David Copperfield, was eventually driven through 27 law-suits in an attempt to protect his earnings from the depredations of his family. Jackie (The Kid) Coogan, who began his career at 18 months, had to file a suit against his family to get back what they had left of his earnings, and in so doing prompted the passing of the Coogan Act which was designed to prevent such abuses in future.
And we all know what happened to Macaulay Culkin and his frustrated-actor father. Not only are the two estranged: 16-year-old Macaulay is now under the authority of a court-appointed guardian, he hasn't made a film for two years, and he won't be involved in Home Alone III. This is a wonderful dream gone terribly wrong.
The anchor-part in Adrian Noble's new film of A Midsummer Night's Dream is taken by a young Briton who bears more than a passing resemblance to Macaulay Culkin, though he won't thank you for saying so. And with good reason, for 10-year-old Osheen Jones could not be more unlike his American semi-lookalike, either in how he works, or in his background.
I visited him in his dressing room between takes last Christmas. He was playing ludo with his tutor, having just finished his academic "term". A prodigious little learner, she said, and particularly good at maths. He told me he had been put up for the part by his local stage school in Berkshire, and that the whole thing was "really good fun".
The comments he passed on his fellow actors were acute, admiration tempered by intelligent criticism; it was clear he was his own man. And he was funny. He picked up a puppet and became a ventriloquist with easy competence.
He told me his parents were pleased for him, "because neither of them is an actor - though my dad sings". Our conversation was cut short when he was shoved back into his pyjamas - this fantasy starts in the protagonist's bedroom - and sent back to work. He would be glad, he said as he went out of the door, to continue this interview at home, "which is just down the road".
A year later I pick up that invitation, and get a variety of surprises. Dad turns out to be the singer-songwriter Howard Jones, seldom out of the hit parade in the Eighties, and currently pursuing his international career as busily as ever. Home turns out to be a group of old cottages beautifully converted into studios and living-quarters, and surrounded by a huge walled garden. The atmosphere is relaxed and convivial; Osheen's younger sister is already a budding comedienne.
He was born in Ireland where Howard was on tour. Hence the name. It should really be spelt Oisin - and may be again soon. When was the first moment they realised their son had talent? "We were in a dressing room in Colorado with three backing singers called the Aphrodisiacs," says Howard. "They started dancing, and one-year-old Osheen tried to dance along with them. From that point on he's always wanted to dress up and do characters." His mother adds: "The sort of thing which dies off in most children when they get older. But somehow it hasn't with him."
Osheen and his sister have a series of pieces which they perform when any potential audience turns up: a version of Cinderella, and sketches from Absolutely Fabulous. At his first school he played Joseph in the Christmas nativity play three years running, and then doubled as Queen Victoria and a crippled boy in a drama-doc about the educationist Maria Montessori. Then, in a shortened version of Shakespeare's Dream, he played Puck: a prophetic experience, and one he greatly enjoyed.
But he left because he "didn't fit in". He wanted to act, and in that school, acting was seen as a peripheral subject. He had been going to Saturday classes at the nearby Redruth Theatre School, and had already done some commercials including one in Switzerland for coffee, and an in-flight film for British Airways. Going full-time to Redruth was the obvious solution.
"Now I do fit in," he says. "Because a lot of us get work." What stars has Redruth produced? "Kate Winslett." So she's a hero? "No, Well, everyone talks about her, and there are big posters of her everywhere." In other words, yes.
Any male stars one might have heard of? No one particular, he replies, but there is a boy called Joe England who will one day be famous.
Why? "He's amazing! He plays fantastic women - in fact, you get fed up because that's absolutely all he wants to play. Over-exaggerated, very rich, Shirley Bassey types." He then proceeds to do such a funny imitation of this Joe England that I look forward to the real thing when it arrives on the box.
"But I play men and women equally." What sort of characters? "People who are over the top, really amazing and bright. I can't stand playing myself, or anyone normal and boring.
"But I don't want to do it for the money or fame: I just love doing it." Here Howard points out that his own career has been useful. "We've been through all this publicity stuff - it's not uncharted territory for us."
So where do Osheen's earnings go? "Into my bank account, which I don't control yet," he says. "I save it all, apart from spending it on jeans if I need them." What's the biggest thing he's bought so far? "A printer for my dad's birthday." His parents explain that he now foots half the bill for his school fees: apparently his idea.
Since being cast in Noble's Dream, he has had many more offers of work. He recently played a hedgehog in the touring production of the National Theatre's Wind in The Willows, and landed a part nobody else at his school wanted to play - as an unhappy bedwetter in a medical video. "Gritty character roles," purrs his father approvingly.
He is in the current ChildLine advert on television: coming back time after time to the phone, which only rings engaged, progressively more battered and scarred. This is a real drama in miniature.
Next week he will be on view at the Barbican cinema, manipulating puppets in a Victorian toy theatre, falling through space, and conjuring spirits into corporeal form.
Noble's idea is a controversial one. If there is a dream, there must be a dreamer, he reasons. And that dreamer must be both naive and knowing, appreciative both of comedy and of the darker elements in Shakespeare's plot.
Osheen was chosen from a large number of applicants, after a series of auditions. I think they made a good choice.
A Midsummer Night's Dream opens at the Barbican on November 29, and goes on national release in January