The remains of all children on the Grenfell Tower missing list have been formally identified 14 weeks after the deadly fire.

Fiona Wilcox, the Westminster coroner, who is overseeing inquests into the victims of the fire, said the identification of all children reported missing was a “huge milestone”.

Sixty inquests have been opened, including those of 11 children, and a further six victims have been formally identified. Police said this week that the total number of deaths may fall from their earlier estimate of about 80.

“It was a huge milestone today to be able to identify all of the children off this [the police] list and although it has taken a long time, 15 weeks, I am satisfied that all of those identities are secure and reliable and I wish to thank all of those who have worked so hard to achieve that and I particularly give thanks to all of those very many people who have been waiting,” Wilcox said in court on Wednesday.

She was speaking at the opening of the inquests into the death of eight-year-old Mehdi El-Wahabi and Rania Ibrahim, 31. As with all previous inquests, Wilcox immediately suspended proceedings to allow the police investigation and public inquiry to progress.

Mehdi’s remains were identified by DNA, and his body was recovered from the 21st floor of Grenfell Tower. The provisional cause of his death was given as “consistent with the effects of fire”.

Before the inquest, his family paid tribute to “a calm and friendly young boy who loved his family very much”.

They added: “He was loved by staff and pupils at his school who held a beautiful memorial and made a plaque in memory of him.”

Mehdi’s parents, Abdulaziz El-Wahabi, 52, and Faouzia, 41, and their eldest son Yasin, 20, have also been confirmed dead at inquests. His 15-year-old sister, Nurhouda, is presumed dead.

The remains of Rania Ibrahim, 31, were recovered from the 23rd floor, where she lived. Her daughters, Fathia, 5, and Hania, 3, are presumed dead. Her husband Hassan was in Egypt at the time of the fire.

Rania filmed harrowing footage from inside her flat on the night of the fire, which she streamed on Facebook Live. In Arabic and English, she spoke of being unable to get out of the block and recited the shahada, the Muslim prayer often said in moments of acute distress or danger.

Coroner’s officer Eric Sword said the provisional cause of her death was “consistent with the effects of fire”.

The work of forensic recovery teams inside the tower is expected to continue until the end of the year. On Tuesday, Scotland Yard said the number of people who died in the fire may “come down a little bit” from its earlier estimate of 80.

Met police commander Stuart Cundy said cases of fraud coming to light, including people reported missing turning out to be fictitious, could be one factor leading to the final death toll being slightly lower.

But, he added, there could still be people with no social or family connection outside the tower, and not on any official lists.