Happy 20th Birthday, Casey Aldridge!

It's official: Levi Johnston is now America's favorite unwed, redneck, teenage baby daddy - Casey Aldridge has turned 20! Happy birthday, Casey!

Jamie Lynn Spears' boyfriend-fiance received the best possible gift on this 29th day of April, too. He's now out of the ICU at a Mississippi hospital.

Aldridge has been up and walking around today for the first time since suffering a head injury in a car accident on Sunday: "He was a little wobbly because that's the first time he's been up since the wreck," says a family source.

Casey was hospitalized after flipping his F-250 pickup truck on the driver’s side on a two-lane road in Louisiana at about 1:30 a.m. Sunday.

Here's hoping he recovers fully and quickly so he can go back to being known for what he first became famous for: boning Jamie Lynn Spears sans condom and knocking her adorable little self up when she was but 16. Ah, young love.

In honor of his birthday, here's a little photo tribute to Casey Aldridge, Jamie Lynn Spears and their daughter, Maddie Briann. Click to enlarge:

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