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Leonardo DiCaprio may have become "son of the year" at the expense of Paris Hilton.

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"The Wolf of Wall Street" actor reportedly outbid the hotel heiress for a pricey handbag at a charity auction in Cannes, France, Page Six reported.

Leo, a source said, "bought the bag for his mom."

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In his winning bid for the 10,000-euro (about $11,300) Chanel bag, Leo outbid other entertainment industry heavyweights, including Sony Pictures Classics co-founder Tom Bernard.

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The charity auction raised funds to bring heart care to underprivileged children around the world.

Both Leo and Paris are in Cannes for the legendary Cannes Film Festival.