Brooke Mueller's family believes she's more "put together" after checking into rehab in November, Breaking Celebrity News can exclusively reveal.

Sydney Wolofsky, her half sister, revealed to Breaking Celebrity News that she plans to stay in rehab for as long as possible — but Wolofsky hopes when she sees her over the summer, it won’t be at her Utah treatment facility!

Breaking Celebrity News previously reported that Mueller, 39, checked herself into a Utah-based rehab facility following a police investigation regarding her health. Her parents rushed to her side after she was briefly hospitalized following the incident, and have assumed responsibility for her twin boys with Charlie Sheen, Bob and Max, 7.

They have stayed near the rehab to keep the boys close to Mueller, as Wolofsky doesn’t know Sheen’s whereabouts.

“I don’t know if he went to Utah or not, but they do talk to him,” Wolofsky revealed to Breaking Celebrity News.

“I know that the boys saw Charlie during Thanksgiving,” she said. “They went over to his place and his parents do a Thanksgiving thing with their side of the family, so they got to see their grandparents and aunts and uncles, and it was really fun for them.”

She added that she spent the holidays with Mueller and the boys and they “were really good.”

“We went skiing with them and it was really awesome,” she said. “Brooke came out and she snowboarded. It was fun.”

“We actually did get to spend a lot of time with Brooke,” she continued. “So Brooke’s in treatment and she’s doing the program, but my mom is allowed to sign her out for a day pass. So on Christmas and the day before Christmas my mom went and got her a day pass. She came and had lunch with the family, and then we had a family dinner and she went back at night. But it was really fun because she saw the kids every day and she came and did a lot of stuff with us.”

“She even made us a huge dinner one night, and I was like, ‘Do you need help?”’ Wolofsky laughed. “And she’s like, ‘No, I got this.’ And I was terrified. But she did a very good job, and I was very impressed with her!”

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