Bjorn was stabbed on Wednesday 29 March and died in hospital five days later, at which point the police opened a murder investigation.
At the time, Sandi called on the culprit to come forward, and she’s now reiterated her plea, while also detailing how the 23-year-old’s tragic death has affected her family.
“It is hard every single day,” she told the Croydon Advertiser. “It gets harder because the person who did this is still out there.
“What I would say to the person who did this is come forward and take responsibility for your crime. We are all human beings, we all bleed the same blood, we all have a passion, surely they have a conscience - so where is it?
The paper adds that the Metropolitan police have said “there is no update at this time” on their murder investigation.
Many of Bjorn’s friends, including grime artist Stormzy, shared their condolences online following his death.
The community also came together for a series of vigils near the spot where he is believed to have been stabbed.