"Jennifer had planned a fun day to celebrate Casper's birthday," a source tells PEOPLE. And the day began with a four-wheeled birthday present: a customized white Dodge Ram truck.
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Lopez "knew that Casper really wanted a truck, and Casper was very excited about the generous gift," says the source.
Lopez also Tweeted: "@BEAUcasperSMART 'Beau has a birthday we're so glad...
Read more on People.com: Jennifer Lopez Spoils Beau Casper Smart With A Big Birthday Gift
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