$1 million a month to raise the kids

Raising kids is getting expensive—especially if they're used to taking private jets to their five homes.

In an escalating divorce battle, Chicago hedge-fund billionaire Ken Griffin says in court papers his wife, Anne Dias Griffin, wants $1 million a month for child-related expenses.

How can three kids under age 10 cost $1 million a month?

Ken Griffin and Anne Dias Griffin attended the Whitney Museum of American Art's fall gala in New York in 2011.
Amanda Gordon | Bloomberg | Getty Images

In his filing, Griffin said Dias is demanding money for her own lifestyle "under the guise" of the children's expenses.

He said those include $300,000 a month for private-jet travel, $160,000 a month for vacation rentals and $60,000 a month for office space and professional staff.

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In a statement, Dias said the filing is "riddled with falsehoods and just another vindictive attempt by Ken Griffin—Illinois' richest billionaire—to punish his family and avoid his clear responsibility under Illinois law to maintain his children's lifestyle."

Dias's statement doesn't dispute the dollar numbers. But she said Griffin is refusing to give the kids "the support to which they are accustomed and entitled under Illinois law."

Sources close to Dias say the nearly $1 million a month was not a demand by Dias, but an accounting of the couple's child-related expenses while they were married. If so, those expenses would likely be required to continue after the divorce under Illinois law.

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In the filing, Griffin said "it is clear that the only exigency Anne sees is the risk that she might have to start spending some of her own substantial wealth to support herself in the opulent lifestyle she desires."

In a previous filing, Dias said she and their children have come to "enjoy a lifestyle reserved only for the very wealthy," including houses in Chicago, Aspen, Hawaii, Miami Beach and New York. They also have "unrestricted access" to two private jets "to travel to the aforementioned homes" as well as other destinations.

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She said the family has a "large group of staff members assisting the family, including extensive household, security and family office employees," and their own company that employs staffers, called "Griffin Family Services."