The youngest performer at this year’s Edinburgh festival is smiling at everyone.

The star of this most unusual Fringe show is seven months old and likes straws, fairy lights, and his squeaky giraffe friend, Sophie.

The nameless baby, bouncing on his grandmother's knee inside a colourful tent at Fringe Venue 27 - Just The Tonic at the Community Project on the Grassmarket - is the extremely happy solo act in the half hour show, Come Look At The Baby.

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As such, the baby - whose identity, and even gender, is being kept private - is the first new born to be at the centre of a Fringe show.

He is not really a stand-up, more of a shakily sit-up, and the only real drama is when he decides he wants to roll of his grandmother's lap.

But, as a representative of his age group, he does a fine job: bewildered and bewildering, delighted, amused and mercurial.

Babies can of course be ratty, smelly, perky, vacant, engaged, hungry, sweet, loud and funny all within a space of about 20 minutes.

However, on The Herald's visit to this show, a piece of "anti-theatre" by Thorium Theatre, the baby - whose name and sex are being withheld by its producers - is, in the main, beatific.

Recently roused from a nap, unplugged from his dummy and accompanied by Sophie (who is inanimate), the baby sits on his doting grandmother's lap, resplendent in stripes and neckerchief, and smiles his toothless smile at its unusual surroundings.

The audience of about 20, who have paid £4, watch the baby and smile and he smiles back at them. One suspects he has been surrounded by grinning adults before.

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Ambient music plays, Christmas lights twinkle, and the undeniably cute little dude, eyes like saucers, regards the strangers with amused semi-interest, and reacts to his granny's kisses and voice.

And that is that for the show: the only song sung is Twinkle Twinkle Little Tiger (a slight variation on the standard) and the only alarming outburst is a wee shriek as the grandmother swirls him about in air.

One audience member, Susan Smith from Leeds, said: "I wasn't actually looking forward to this, I was worried the baby might be grumpy, or angry, or I would feel that the baby was somehow exploited, but actually looking at the baby, it was such a calming experience. And he was so interested in us."

Of course as the seven month old human smiles and plays with his toy, cosseted by his grandmother and bathed in music, warmth and love, it is hard not to compare these tranquil surroundings with the world outside, and, some observers may say, the pigs ear us adults are making of it.

In the meantime, the child has spent half an hour being a small human: smiling, laughing, playing and eyeing with wonder the stars above him and the music around him.

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Meanwhile, the audience, who this show is probably really about, has perhaps temporarily dropped its sullen thoughts of Brexit, Trump, IS, terrorism, grief and recession, for half an hour with an innocent who likes squeaking his toys and being kissed by his grandmother.

Which is tonic enough for one rainy day at the Fringe.