He suffered critical injuries following an incident in Thurnscoe last Friday, and he subsequently died two days later on June 7.
Detectives are appealing for information regarding two specific incidents in Thurnscoe last week as they look to build up a picture of the circumstances leading up to Stephen’s death.
Detective Chief Inspector Mark Oughton, the senior investigating officer, said: “My appeal for information is three-fold.
“It begins with an incident that took place in Derry Grove Park before 8.30pm on Thursday June 4, when police received a report that Stephen - who was also known locally as Squeek - was unconscious in the park.
“He was checked by paramedics and returned home a short time later.
“The second part of my appeal is for information about the suspected assault that took place the following day, Friday, in the Houghton Road area of Thurnscoe, at around 7pm.
“Police received a call from ambulance staff reporting concerns for Stephen, who had been taken to hospital with a serious head injury.
“Lastly, we want to hear from anyone who may have seen Stephen in the Thurnscoe area at any time on either Thursday or Friday.”
Five people are currently in police custody after being arrested on the suspicion of murder.
A 36-year-old man, a 34-year-old man and two 15-year-old boys - who were arrested on Saturday of suspicion of assault and bailed, have now been re-arrested on suspicion of murder.
A 35-year-old man is also under arrest on suspicion of murder.
A sixth person, a 35-year-old man, was arrested on suspicion of murder on Sunday, but has since been released on police bail.
Anyone with information - particularly in relation to the two incidents above - should call 101 quoting incident number 650 of June 5.
Stephen’s family are being supported by specialist officers and have asked for their privacy to be respected.