Bill Gates children understand why he'll be leaving his $120 billion fortune to his foundation

Bill Gates said his three children understand why he has pledged to leave his £70 billion (NZ$120b) fortune to charity when he dies.

In a revealing insight into his private life, the Microsoft founder, 60, said his children are "proud" of his decision to dedicate his money to helping the world's poorest.

Gates said that instead of billion-dollar trust funds, his two daughters and son will be given a "great education" to help kick-start their own careers.

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Happy 100th birthday, @nationalparkservice! So many of my favorite family trips, both as a kid and now as a mom, have been to the national parks. Thank you for everything you do to ensure that our country’s most beautiful places will continue to be enjoyed for generations to come. #NPS100 #findyourpark

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But the business mogul did say there would still be a financial safety net in place, adding: "They are never going to be poorly off".

Speaking on This Morning, Gates said: "Our kids will receive a great education and some money so they are never going to be poorly off but they'll go out and have their own career.

"It's not a favour to kids to have them have huge sums of wealth. It distorts anything they might do, creating their own path."

Gates and his wife Melinda, 52, have three children together, Jennifer, 20, Rory, 17, and Phoebe, 14.

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To the best dad, partner, and photobomber I know, happy #fathersday.

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Rory and Phoebe are believed to at school and live at home with their parents outside Seattle, Washington.

The Gates will only pass on a fraction of their vast wealth to their children.

The rest will go to their charity, the Bill And Melinda Gates Foundation, which funds health and education projects around the world.

In a rare insight into family life, Gates told This Morning presenters Holly Willoughby and Ben Shephard his children are behind the decision.

He said: "This money is dedicated to helping the poorest. They know that, they are proud of that, they go on trips with us to see the work that's being done."