The woman arrested on suspicion of child neglect after four children died in a house fire in Sutton has been bailed.
The 27-year-old will return to a south London police station in mid-January, the Metropolitan Police said.
Leyton and Logan Hoath, aged three and Kyson and Bryson Hoath, aged four died after the blaze broke out at their home in Collingwood Road on Thursday night.
Firefighters said they were home alone when they arrived at the scene.
Media reports have said the children’s mother, Deveca Rose, was out shopping when the blaze started.
According to The Sun, she was jeered when she returned home to find emergency services trying to resuscitate her sons on the pavement.
One neighbour said: “There was an angry reaction from the crowd when the mother arrived home.”
The boys’ father has spoken of the “devastating” impact of the incident on his family.
It came as a 27-year-old woman was arrested on suspicion of child neglect after the blaze ripped through the mid-terrace house on Collingwood Road, Sutton shortly before 7pm on Thursday.
Mr Hoath, said in a statement given to MailOnline on Friday: “Myself and my family are utterly devastated by this tragic loss.
“They were bright, caring, loveable boys, but most of all Sons, Brothers Grandsons, Great Grandsons, Nephews and Cousins.
“We would like to thank all the emergency services who did so much to try and save our boys, and also the local community who have come together at this difficult time.
“I would ask that my family are given time to grieve in private.
“They will be forever in my heart and thoughts, love Dad.”
Chief Superintendent Dave Stringer, borough commander for Croydon, Bromley and Sutton Police, confirmed that the children were related.
He told reporters at the scene on Friday afternoon: “There was nobody else inside the property at the time of the fire.”
He said the Met and the London Fire Brigade are investigating the cause of the blaze.
The woman arrested on Thursday night on suspicion of child neglect remains in police custody, the police chief said.
In a post on Facebook, Jason Hoath wrote: “I am devastated to say that the horrendous house fire that took place in Sutton last night leading to four children loosing (sic) their life’s (sic) were my amazing smart and beautiful grandsons.
“(They were) taken too soon they will always be in our hearts and thoughts.
“Boys I love you forever. Grandad xxx”