LUCKNOW: Prateek Yadav, the stepbrother of Akhilesh Yadav and husband of BJP leader Aparna Yadav died on Wednesday morning. He was 38 years old.Sources said Prateek Yadav was brought to Civil Hospital in Lucknow around 6am, where doctors declared him brought dead. The exact cause of death has not yet been disclosed.Prateek was the younger son of late Mulayam Singh Yadav. Unlike Akhilesh Yadav, he was not active in politics, though Aparna Yadav remains an active BJP leader.A post-mortem examination is being conducted and the exact cause of death is expected to be known after the report is released.(This is a developing story)