Sheen was banned from contacting his wife after a feud in Aspen, Colorado, on Christmas Day, which landed him in police custody.
The star is now facing charges of second-degree assault, menacing and criminal mischief amid allegations that he threatened Mueller with a knife during the heated argument.
Sheen is reportedly keen to have the protection order lifted, while Mueller's attorney filed a motion to have the order's no-contact clause removed.
According to her lawyer, Yale Galanter, Mueller recently flew back to the city from her rental house in Aspen.
Sheen, meanwhile, remains in Los Angeles, where he's at work on his hit sitcom Two and a Half Men.
Galanter tells People.com, "Brooke has personal matters and places to take the twins in Los Angeles, so she went home for a few days. Charlie is staying with a friend for the time she is there."
Mueller and Sheen are expected to return to Colorado for a hearing on Jan. 20.
Galanter adds, "Brooke still has her house in Aspen and will be back next week. So will Charlie. But not together."
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