The main characters in Grey’s Anatomy have had difficult personal lives, especially when it comes to their families, and Mark Sloan (Eric Dane) was no exception. Mark went through many ups and downs in his personal life, so it’s easy to forget that he had two children – but what happened to them? Although the quality of Grey’s Anatomy has decreased over the years, it continues to be one of the most successful medical dramas in TV history, and it has kept a loyal fanbase that keeps following the stories of Meredith Grey (Ellen Pompeo) and company quite closely.

Grey’s Anatomy focuses on the lives of surgical interns, residents, and attendings as they do their best to balance their personal and professional lives, which always overlap and make way for a lot of drama inside and outside the hospital. Grey’s Anatomy is led by Meredith Grey, who started as an intern at Seattle Grace Hospital and has now become head of general surgery at the same hospital, now named Grey Sloan Memorial Hospital. Through Meredith, viewers met some of her fellow interns – such as Cristina Yang (Sandra Oh) and Alex Karev (Justin Chambers) – and some of the attendings that impacted her life in different ways, among those Mark Sloan.

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Mark Sloan was the Head of Plastic Surgery at Seattle Grace Mercy West Hospital, Derek Shepherd’s (Patrick Dempsey) best friend, and the on-again-off-again sentimental partner of Meredith’s half-sister Lexie (Chyler Leigh), though she wasn’t his only partner in Grey’s Anatomy. Mark’s personal life was the main focus of his arc, but two very important people in his life got lost in the drama: his daughters.

Why Mark Sloan's Daughters Disappeared In Grey's Anatomy

Grey's Anatomy Sloan Riley

Many years prior to the events of Grey’s Anatomy, Mark had a relationship with a woman named Samantha, and when she got pregnant, Mark gave her some money and assumed she had an abortion, but that never happened. Their daughter, Sloan Riley (Leven Rambin), was 18 years old when she made her first appearance in Grey’s Anatomy season 6 and she was pregnant. As Samantha kicked her out of the house, she flew to Seattle to meet her father and revealed to him and Lexie that she was pregnant. After some complications with her baby that required surgery, Sloan decided to give her son up for adoption, despite Mark telling her to keep the baby and give him to him to raise. Although she had already chosen the parents for her baby, Sloan started to hesitate about the adoption, and what happened to her baby and her after giving birth and Mark showing his support to her is unknown.

Mark later had another daughter, Sofia, with Callie Torres (Sandra Ramirez). After breaking up with Arizona Robbins (Jessica Capshaw), Callie moved in with Mark and they had a short fling that resulted in Callie becoming pregnant with Mark’s child. Arizona returned and got back together with Callie, and she agreed to raise the child with her, even though she wasn’t on board with Mark now being a permanent part of their lives. Sofia was delivered 16 weeks early as a consequence of a car accident Arizona and Callie got into, and after various health complications, she made a full recovery. Sofia was still very young when Mark died in Grey’s Anatomy season 9, but her story continued as Callie and Arizona were still part of the series. After a custody battle that Arizona won, Sofia split her time between New York with Callie and Seattle with Arizona, ultimately choosing to stay in the latter. However, she missed Callie and life in New York, leading Arizona to move there so Sofia could be with both of her moms. With Sloan Riley having no more links to Grey’s Anatomy after Mark’s death and Sofia living with her mothers in New York, it’s understandable that they disappeared, though it would have been interesting to know what happened to Sloan and her baby, and how she dealt with Mark’s death.