IT’S a showbusiness marriage made in heaven: high octane American entertain- ers (one a winsome former 1970s’ teen idol) meet thousands of near-hysterical post-menopausal Merseyside women.

While most of the female members of the audience have probably gone through the change, Donny and Marie Osmond don’t appear to have changed at all in half a century of showbiz.

However, sister Marie made an early reference to her roller-coaster body temperatures while saying “Hi to my favourite fan” – an electric one at the footlights.

Brother Donny, meantime, lying on the stage after an exhausting dance routine, gasped: “My mind’s back there in the 1970s, but my body is not.”

But this is all part of a show so slick it could asphyxiate a flock of seagulls. For their ages, Donny, 55, and Marie, 53, are fantastic, delivering a finely-honed two hours plus of sheer showbiz pizzazz.

Back in the 1970s, Donny and his four Osmond older brothers made the template for every boy band since, but the family were hard at it from the early 1960s with Donny and Marie’s debut on Andy Williams’ TV show at the age of five and three years respectively.

The Liverpool Arena show was the final date of a UK tour celebrating the siblings’ five decades in show business.

Marie baldly stated she knew all the women were there to see her brother and asked if any men came to see her? Three hands waved shakily and someone called Al was dragged up for an ad hoc duet.

“Awesome Al”, as Marie dubbed him, was so good that you wondered if he was a plant along with the siblings’ (surely) rehearsed, but very amusing ad-libs?

Yet Al looked horrified when Marie threw his jacket off-stage and he squawked: “Eh, me mobile’s in that!”

Later Donny looked truly surprised (oh yeah?) when a line from the musical Joseph, in which he pleads “Do what you want with me” caused audience uproar.

All their big hits from the 1970s were given a good airing. While the performers were in excellent voice, the audience put up a counter attack by practically out- singing Donny in Puppy Love, Love Me For A Reason and Like A Yoyo.

We attended the show as my wife wanted to right the wrong of being three times denied the chance to see her idol Donny in the 1970s. For me the revelation was Marie, who is a charismatic power- house performer, with a voice that ranges from her country and western hit Paper Roses to a rendition of Nessum Dorma.

Between them, they seem to be able to tackle any genre of singing. As Marie said: “We do what used to be variety, but is now called attention deficit disorder.”