Harry Styles' stepfather Robin Twist has died aged 57 after a "long cancer battle".
The singer acted as the best man at Robin's wedding to his mum, Anne Cox, in Congleton, Cheshire, in 2013.
The family has released a statement saying: "Harry's stepfather, Robin Twist, sadly passed away this week after a long battle with cancer. The family asks for privacy at this time."
#RIPRobin has been trending on Twitter and fans have been paying tribute.
Robin and Anne had just celebrated their fourth wedding anniversary.
The pair got married in a gap in Harry's touring schedule with One Direction in Lisbon and Mexico City on the group's Take Me Home Tour.
Robin Twist has two children from a previous marriage, called Mike and Amy.
But he helped raise Harry and his sister Gemma when they were teenagers after he and Anne started dating.
Liam Payne has paid tribute to Robin saying his heart went out to Harry and his family.
Louis Tomlinson's mum, Johannah Deakin, died in December from an aggressive form of leukaemia.