The baby of Shamima Begum, a British-born teenager who fled London to join the IS, has died in Syria.
The death has been confirmed by the US-backed Syrian Democratic Forces, who declined to specify how or when it happened.
According to the medical certificates obtained by the BBC, the three-week-old boy died of pneumonia.
Shamima, who was stripped of her UK citizenship despite her wish to return, had previously lost two other children, apparently from illness and malnutrition.

US Epstein files release highlights Clinton, makes scant reference to Trump
Bangladesh holds state funeral for slain youth leader amid tight security
US hits ISIS in Syria with large retaliatory strikes, officials say
Pakistan court hands Imran Khan, wife 17-year jail terms in another graft case
Seven elephants killed in India train accident
Israeli attack on school shelter in Gaza City kills 5 Palestinians
Nine injured in attack in Taipei, media reports
Putin offers no compromise on Ukraine, says EU 'robbery' failed
