The teenager will be buried in Brixton on Friday without his family present as his mother and six siblings are forced to self-isolate.
Family friend Mohammed Motlib says the family are "heartbroken" at Ismail's death and described him as a "gentle and kind" child
Mr Stephenson said: “Shaykh Sharif Zain will be leading the funeral and I will be delivering a short speech for the Abdulwahab family and a few close family and friends.
“We hope that we can send a live stream of the funeral to his mother and siblings so they can be there remotely, but they are obviously devastated that they can’t be there in person again.
“It’s extremely upsetting for everyone involved, but they have been very moved by the warmth and very positive messages of support from people following their appeal.”
Ismail, who had no apparent underlying health conditions, was described by his family as a “gentle and kind” boy with a “heartwarming” smile.
He tested positive for Covid-19 last Friday, a day after he was admitted to King’s College Hospital.
On Wednesday, the NHS confirmed a 13-year-old with no known underlying health condition was among patients who had died after testing positive for Covid-19.
Mr Stephenson, college director at the Madinah College where Ismail’s sister works, set up the GoFundMe page to raise money for funeral costs and for the family, who also lost Ismail’s father to cancer.
By Friday morning more than £67,000 had been raised, far exceeding the £4,000 target.
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