Mary Cosby Gives Update on Son Robert Jr. After Emotional Substance Abuse Admission

While appearing on Watch What Happens Live with Andy Cohen Wednesday, The Real Housewives of Salt Lake City star revealed her son sought treatment for drug addiction and is currently home from rehab.

Calling him a "new person," Mary got visibly emotional as she spoke about her son.

"Rob is doing so good," she said while choking up. "I am so proud of him, so proud of him."

Mary said the 21-year-old stayed at the rehab center for one month and completed his program.

"He did an excellent job," she raved. "He came out a new person."

When asked about Mary's emotional conversation with Robert Jr. that aired in last week's episode of RHOSLC, which saw the pair candidly discuss his addiction issues, Mary revealed that the raw and real moment was not planned.

"It wasn’t planned," she said while starting to cry. "We just came together, Robert and I, and I said, 'We're going to do this because we're going to help someone.'"

Mary explained that her son did "not plan what he was going to say" in front of the cameras and neither did she.

"I just said what I felt," Mary said through tears, prompting Cohen to reach over and take her had.

"You did great," he assured the reality TV personality.

Mary also shared an update on Robert's wife, who she said also sought treatment at a rehab center, telling WWHL viewers that she is "still in there."

As for Robert Cosby Sr., while he hasn't been seen on the show this season, Mary said he helped her and their son throughout the ordeal, drawing on his own experiences with drugs to help "guide" Robert Jr., and help him get "better."

The update comes after last week's episode of RHOSLC, where Mary asked her son to tell her the "honest truth" about what was going on with him after a period of odd behavior.

It's then Robert Jr. admitted to taking Xanax -- and a host of other drugs -- over the course of several years.

"I started buying it," he said of the prescription drug, which is used to help those with anxiety. "Then I started doing Xanax with acid, and then Molly with Xanax, because I really like Xanax, so I mixed it with everything, Xanax and cocaine."

While the confession came as a surprise to Mary, with her son, at one point, even admitting to wanting to end his own life, the pair came to a resolve, as Robert Jr. promised to seek help and his mother committing to helping him -- with a little tough love -- through it.

"I can help you," Mary pleaded with her son. "I can try to help you, but you have to help yourself, because I'm not gonna support it. I'm not. You know I'm not."

RHOSLC airs Wednesdays on Bravo.