Leah Messer took and passed a drug test during her recent custody battle.

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On Dec. 8, during a custody hearing for twins Aleeah and Aliannah, the Teen Mom 2 star was ordered to take a hair follicle drug test and passed.

“She was a nervous wreck,” a family insider told In Touch Weekly on Thursday. “When the results came back, she was ecstatic. There’s no way in hell she would ever give Corey and [his current wife] Miranda primary custody of the girls.”

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Messer and Simms began fighting over the custody of their twins in 2014, after Simms became aware of Messer's questionable behavior on Teen Mom 2. During the series' fifth season, Messer began taking medication for her anxiety, and while the pills were prescribed, she didn't react to them well, and admitted to feeling "druggy" as cameras rolled.

Although the scene certainly didn't work in Messer's favor when it came to her custody battle, In Touch Weekly's source claims the reality star and mother of three is in a much better place these days, and is focused on being the best mom she can be to her twins.

“She’s telling everyone she’s determined to make a complete turnaround,” a second source told the magazine. “She says she’s ready to clean up the wreckage from her past.”

Messer and Simms are currently filming Teen Mom 2 season 6, which will premiere later this year on MTV.