Simon Cowell invites terminally ill children to rehearsals for her shows.

The kind-hearted media mogul is patron of UK children's hospice charity Shooting Star Chase, which helps sick kids and whenever his popular reality TV shows such as 'The X Factor' and 'Britain's Got Talent' are filming he thrills the youngsters by having them come to meet the acts and watch rehearsals.

A source told The Sun newspaper: "Simon might be a multi-millionaire but he does an awful lot for charity. And he doesn't just donate money, he gives his time."

Simon also hangs out backstage with the children and the usually-serious judge even plays games with the youngsters.

The source added: "These kids love coming down to the show and he makes it special by teasing them and playing games with them. He enjoys it and they have a day they will never forget. He lets them takes photos of them doing silly things. He's great with them."

Although he plays up his Mr Nasty image on 'X Factor', Simon often undertakes a number of good deeds.

He previously paid off the mortgage of the parents of a cancer-stricken girl, writing them a cheque for £100,000 to help them cope.

Simon said at the time: "I never knew that doing good could feel so good.

"It doesn't stop here. If there's any problem, I'm her guardian angel now."

It was also revealed Simon - who is believed to be worth over £100 million - will leave £90 million to charity in his will.

The 52-year-old star, who has no children, will leave the mammoth sum to a selection of organisations helping children and animals.