But while Mueller is indeed staying at her ex-husband's home with their twin sons, her stepdad exclusively tells E! News that she most certainly has not moved back in for good.
So if she's not hanging around because she loves a good party, why is she there?
"He's buying her and the kids a house," Jon Fiore explains. "Brooke is temporarily staying with him until the house is ready for her and the boys to move into, which should be any day now. Brooke and Charlie are still friends. She is not living with him, but she is staying there until her house is ready."
A source tells E! News that Sheen purchased the new house because he wanted his sons to live closer. Mueller, who had been living in Los Feliz, found a buyer for that house, hence her temporary roommate arrangement.
"Brooke is staying at the end of the house from Charlie. It's a big house," the source says.
But while Sheen's been living it up with his Major League screenings, and was recently photographed with a rumored new gal-pal, the source says that Mueller "won't be having any male suitors to Charlie's home."
In fact, she and her ex, who's due back at work on Monday, are currently on vacation, along with a couple of Sheen's lady friends, according to the insider.
"Brooke went along to get some rest and relaxation, she loves Charlie as a friend and as the father of her children," the source says. "The boys are at home with the nannies while their parents are on vacation."
—Additional reporting by Aly Weisman