Reese Witherspoon Wishes Her Son a Happy 3rd Birthday with an Adorable Photo

Reese Witherspoon's littlest look-alike is growing up so fast! The actress took to Instagram to wish her youngest son, Tennessee Toth, a happy third birthday, and we just can't handle the cute.

"Happy Birthday Sweet boy! 3 is a magic number" the Oscar-winning mom captioned the photo of her adorable towhead posing in the sand wearing bright blue sunglasses.

Happy Birthday Sweet boy! 3 is a magic number 🎈🎈🎈

A photo posted by Reese Witherspoon (@reesewitherspoon) on Sep 26, 2015 at 2:05pm PDT

Not long after, Witherspoon posted a snap of the lucky tike's birthday cake, a chocolate confection topped with a fleet of miniature construction trucks that would make any young boy drool.

It's all about that cake🎂

A photo posted by Reese Witherspoon (@reesewitherspoon) on Sep 26, 2015 at 5:43pm PDT

Tennessee isn't the only member of Witherspoon's brood to celebrate a birthday recently. Two weeks ago her daughter, Ava Phillippe, turned 16 years old—an event the proud mom marked in a similar fashion, on Instagram, of course!

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