Brooke Mueller -- She May Not Get Twins Back for A Year

Brooke Mueller thinks she's going to get her kids back when she leaves rehab, but according to sources connected to the L.A. County Dept. of Children and Family Services ... she may not get the kids back for at least a year.

Brooke has been in rehab around 20 times ... in other words, it never sticks -- at least not so far. Our Brooke sources are confident the judge will return twins Bob and Max to her when she exits rehab, and her family is willing to do what it takes to reassure the court that the kids will be fine. If that means a family member living with Brooke ... we're told that will be offered.

But other sources tell TMZ ... DCFS feels it's too risky to return the kids to Brooke until there's proof she can function clean and sober over a period of time, and we're told that time frame is a year, and possibly longer. Our sources add ... DCFS will allow meaningful visitation between Brooke and the kids, but not custody until there's proof she's on the straight and narrow.