Casey Aldridge Walks for First Time Since Car Wreck

By Mark Lambert

04/29/2009 at 05:20 PM EDT

Casey Aldridge has been released from intensive care and is walking around for the first time since suffering a head injury in a car accident on Sunday.

"He came out of ICU," a source tells PEOPLE, adding that doctors are hopeful they'll soon be able to discharge Aldridge – the father of Jamie Lynn Spears's 10-month-old daughter Maddie – from the University of Mississippi Medical Center in Jackson, Miss.

Aldridge, who turned 20 on Wednesday, was up "walking around twice [on Tuesday]," says a source close to the family. "He was a little wobbly because that's the first time he's been up since the wreck."

As for how Spears has been handling the incident, a friend tells PEOPLE she's holding up well. "I've been very proud of her," says the source. "I'm really impressed."

Aldridge 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.

The accident – during which three of the five occupants, including Aldridge, were ejected from the truck – occurred after a bachelor party for Aldridge's cousin at nearby Lake Bruin on Saturday, according to a source. The two other passengers thrown from the truck suffered less serious injuries.

• With reporting by RUTH LANEY

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