JUNEAU — A custody case between Bristol Palin and Levi Johnston has been closed, and an attorney says the two likely will work out any future differences regarding their 3-year-old son on their own.

Alaska court records show the case involving Sarah Palin’s grandson Tripp was closed this month after a lack of activity.

Johnston attorney Rex Butler said Monday the best way to interpret the development is that the parties likely will resolve any problems themselves. An attorney for Bristol Palin didn’t immediately respond to a request for comment.

Bristol Palin and Johnston initially battled over custody. But they agreed in 2010 that Bristol would have primary physical custody and the two would share legal custody, subject to Bristol’s resolution if they couldn’t agree, then-Palin family attorney Thomas Van Flein, said at that time. Johnston was given visitation, and he agreed to pay child support.

An automatic notice of pending dismissal was posted in July because of a lack of activity in the case.

Bristol Palin and Tripp appeared on the recent Lifetime series “Bristol Palin: Life’s a Tripp,” in which Johnston’s presence in his son’s life, or lack thereof, was part of the story line.

Bristol Palin and Johnston were thrust into the national spotlight in 2008, as unwed teenagers expecting a baby, when Sarah Palin was the Republican candidate for vice president. The two have had a tumultuous on-again, off-again relationship, including called-off engagements.

Both have gone on to write books, and Bristol Palin also has appeared on “Dancing with the Stars.” Johnston recently had a baby with his girlfriend.

In a blog post Monday, Bristol Palin said that while she doesn’t have “much interaction” with Johnston, she is happy for him with respect to his new daughter.

“A child is a blessing and I know they are experiencing the joys (and challenges!) of having a newborn,” Bristol Palin wrote. She said Tripp sent the new baby flowers, “and we both wish all the best for her.”