Shamima Begum‘s sister has pleaded with Home Secretary Sajid Javid to allow the Isis bride’s newborn son to come to Britain.
Ms Begum’s family also said they will challenge his move to revoke her British citizenship.
Renu Begum, writing on behalf of her family, said they were “shocked and appalled” by the “vile comments” the 19-year-old has made to the media, but they have a duty to help her.
In a letter to the Home Secretary, the family asked for help to bring Ms Begum’s baby back to the UK, saying he is a “true innocent” who should not “lose the privilege of being raised in the safety of this country”.
Ms Begum fled London four years ago at the age of 15 to join Islamic State’s self-proclaimed caliphate in Syria, but has now said she wants to return to the UK with her son – prompting Mr Javid to start the process to revoke the teenager’s British citizenship.
In the letter, Shamima’s family said they have had no contact with her and had only learned she had given birth to a boy through media reports.
Her family’s letter said they had made “every fathomable effort” to block her from entering IS territory.
“That year we lost Shamima to a murderous and misogynistic cult,” her sister wrote.
“My sister has been in their thrall now for four years, and it is clear to me that her exploitation at their hands has fundamentally damaged her.”
The family added: “We are sickened by the comments she has made, but, as a family man yourself, we hope you will understand that we, as her family cannot simply abandon her.
“We have a duty to her, and a duty to hope that as she was groomed into what she has become, she can equally be helped back into the sister I knew, and daughter my parents bore.
“We hope you understand our position in this respect and why we must, therefore, assist Shamima in challenging your decision to take away the one thing that is her only hope at rehabilitation, her British citizenship.
“Shamima’s status will now be a matter for our British courts to decide in due course.”
Sajid Javid’s attempted removal of Ms Begum’s British citizenship – a move only permissible under international law if it does not leave the individual stateless – came amid heated debate over whether she should be allowed to return to Britain.
Many have argued the teen should not be allowed to return, while others say she should face prosecution and attempts should be made to deradicalise her.
It had been speculated that the 19-year-old may have citizenship in Bangladesh but the Begum family’s lawyer Tasnime Akunjee said she was born in the UK, has never had a Bangladeshi passport and is not a dual citizen, which was confirmed by the Bangladeshi minister of state for foreign affairs.
Asked about the situation on ITV’s Peston, Mr Javid said: “I’m not going to talk about an individual, but I can be clear on the point that I would not take a decision and I believe none of my predecessors ever have taken a decision that at the point the decision is taken would leave that individual stateless.”
He also suggested to the Commons that action to bar her from returning will not impact her son’s rights.
The British Nationality Act 1981 provides the Home Secretary with the power to strip people of citizenship if it is “conducive to the public good”.