A Closer Look at RHOSLC Star Mary Cosby's Son, Robert Cosby Jr.

Mary Cosby’s son Robert Cosby Jr.; Mary Cosby visits SiriusXM Studios on September 9, 2025 in New York City.
Credit:

Mary Cosby/Instagram; Jason Mendez/Getty

Key Takeaways

Mary Cosby and her husband, Robert Cosby Sr., welcomed their son Robert Cosby Jr. in the early 2000s.
Both mother and son have appeared on The Real Housewives of Salt Lake City, where Robert Jr. has shared his struggle with substance abuse.
The couple is also the subject of the TLC series The Cult of the Real Housewife.

Mary Cosby’s son, Robert Cosby Jr., has been a notable figure on The Real Housewives of Salt Lake City since the show’s inception in 2020, where he shares his personal challenges, including substance abuse issues.

Born in 2002 to Mary and Robert Cosby Sr., Robert Jr. is the only child of a couple that leads the Faith Temple Pentecostal Church in Salt Lake City. Mary revealed on the show that Robert was born after four years of attempting to start a family.

“He was like the perfect child,” Mary recounted during a confessional, illustrating that Robert excelled academically, achieving straight A’s throughout his schooling.

Over the course of the show, Robert Jr. has candidly discussed significant life events, including his first girlfriend and a subsequent courthouse wedding. However, he has also opened up about serious issues, such as his struggle with substance abuse and suicidal thoughts.

Mary has remained a strong support for her son as he navigates his sobriety journey, which she described as “a hardcore road.” During a September 2025 appearance on SiriusXM’s Reality Checked, she expressed her unwavering encouragement: “I have hope and I believe in him. … I know he’s got all the tools and he’s got all the will.”

### His Only Child Status

Robert Jr. is the only child of Mary and Robert Sr., who wed in September 1998. His name, Robert Clinton Cosby Jr., reflects his father’s heritage. Mary shared, “When I had my son, I went into a whole other level of love.”

Mary also explained that she plays a protective role, describing herself as a “helicopter mom.” The family frequently traveled to various destinations for Robert Jr.’s birthdays, showcasing their dedication to providing him opportunities for exploration and growth.

In an effort to improve his upbringing, Mary moved the family from Utah to New York for eight years, citing the desire for Robert Jr. to experience a diverse education.

### Current Living Situation

Robert Jr. resides at the family’s Salt Lake City home, alongside his parents. Although he initially aspired to be a fashion designer, as of 2024, he continued to live at home, a situation Mary characterized as her fault due to his sheltered upbringing.

“I just feel like he’s very sheltered, and I feel like that’s my fault,” she admitted on the show. “So that’s why I don’t mind him staying home.”

### Recent Marital Developments

In August 2022, Robert Jr. secretly married his girlfriend, Alexiana Arian Smokoff, in a Utah courthouse—a secret maintained from his parents for nearly a year. During the season 4 premiere of RHOSLC, Mary addressed the rumors and later confirmed the marriage after Robert Jr. admitted to the nuptials.

Despite sharing a home, Robert Jr. and Alexiana’s marriage went unnoticed by Mary for a notable period, sparking further intrigue. “They both live in my house, but I don’t see them much,” she remarked.

### Substance Abuse and Mental Health

Robert Jr. has been candid about his long-standing issues with drug addiction, which includes the use of prescription and recreational drugs. His revelations came to light during a season 5 episode, where he disclosed using Xanax since the age of 16. Mary faced the emotional burden of his struggles, often expressing regret for not recognizing the signs sooner.

“If I don’t blame myself, whose fault is it? I feel I’m responsible,” she stated. Following a month-long rehab stint, Robert Jr. emerged, with both him and his wife undertaking the journey together, a development Mary described as a turning point.

### Legal Troubles

Robert Jr. has encountered multiple legal issues, including a DUI arrest in 2022. Most recently, in September 2025, he was arrested on various charges, including assault and criminal trespassing. These incidents were said to stem from an altercation involving his father-in-law, with reports detailing a chaotic scene.

Despite these challenges, Mary reflected on her son’s arrest as a “blessing in disguise,” suggesting he needed a wake-up call regarding his life choices.

“It was for his good,” she emphasized.

In November 2025, Robert Jr. faced further complications as his wife filed for divorce just two weeks after he was arrested for violating a protective order.

### Maternal Bond

Through all the highs and lows, Mary Cosby describes her son as her “everything.” In heartfelt conversations regarding Robert Jr.’s struggles, she has expressed deep affection and commitment to supporting him. “You have to know I love you more than anything,” she told him.

Robert Jr. candidly shared his struggles with his identity during these times, stating, “I felt like a stain,” evoking a sense of urgency in Mary’s reflections on her son’s well-being.

Mary’s unwavering support, coupled with Robert Jr.’s ongoing journey, underscores a powerful story of resilience and the enduring nature of familial love.