Grey's Anatomy: Is Sloan Riley really Mark's daughter?

Sloan's pregnancy was not without complications. Her baby had bands of amniotic tissue around his legs, causing concern for Mark. Addison was brought in to perform surgery on the baby in utero, but Mark ultimately decided to fly to Los Angeles to let Addison finish the surgery. Sloan's health took a turn for the worse, and she had to undergo another surgery to save her and the baby. Despite these challenges, Sloan ultimately decided to keep the baby, with Mark's support.However, Sloan's journey as a mother and her relationship with Mark was not without its challenges. She eventually left without telling Mark, feeling the need to be someone else's baby. It is unclear what happened to Sloan and her baby after giving birth, as well as how she dealt with Mark's death. The show introduced another daughter of Mark, Sofia, who was delivered prematurely and faced health complications but eventually made a full recovery. Sofia's story continued even after Mark's death, with a custody battle and eventual split time between New York and Seattle with her mothers Callie and Arizona.While there is no concrete evidence to suggest otherwise, it is possible that Sloan Riley may not be Mark's biological daughter. This ambiguity may stem from the lack of further development of Sloan's storyline after Mark's death. The focus of the show shifted to Sofia and her journey with Callie and Arizona. Sloan's absence and the lack of information about her and her child's whereabouts leave room for speculation.In conclusion, the available evidence suggests that Sloan Riley is Mark Sloan's daughter. However, the lack of further development of her character and storyline leaves room for uncertainty. Fans of Grey's Anatomy may continue to debate and question the true nature of Sloan's relationship to Mark, but until further information is provided, it remains an open-ended question.