The youngest woman to be convicted of plotting a terror attack on British soil has been jailed for life, with a minimum term of 13 years.
Safaa Boular, 18, of Vauxhall, London, was convicted of preparing acts of terrorism and attempting to travel to Syria to join Islamic State militants.
She had been groomed online by her IS fighter “husband” who was later killed.
Boular was part of the UK’s first all-female terror cell with her mother and sister, who were both jailed in June.
An Old Bailey jury found she had planned to die in a suicide bombing in Syria – but when that was not possible, she hoped to attack the British Museum.
Passing sentence, Judge Mark Dennis QC told Boular her views were “deeply entrenched” and “she was old enough to make her own decisions and her own choices”.
“However much she may have been influenced and drawn into extremism, it appeared she knew what she was doing and acted with open eyes,” he said.
Defence barrister Joel Bennathan QC said Boular had a neglectful mother and a radicalised sister, describing her as a child from a damaged home.
He said she had type 1 diabetes and was “sexually groomed” and radicalised by a British IS recruit.
Mr Bennathan said her teenage years had been chaotic but there had been a “genuine” change in her character since her arrest.
Boular, who presented herself at trial in Western clothing and declared herself deradicalised, showed no emotion as she was sentenced.
Aged 16, Boular was radicalised online in the wake of the 2015 Paris terror attacks, when she was sitting her GCSEs.
She met British IS fighter Naweed Hussain on Instagram and after three months of chatting, she declared her love for him with an online marriage ceremony.
The court heard how she had wanted to join Hussain in Syria, but her plan was thwarted when British security services became involved and confiscated her passport.
After she was stopped from going to Syria, she revealed her plans for a grenade and gun attack on the British Museum to MI5 officers posing as extremists.
Boular was arrested and her family home was bugged.
Despite being in custody, she continued to talk to her sister and mother about an Alice in Wonderland-themed tea party – code for another attack.
At the Old Bailey her sister, Rizlaine Boular, 22, who was to carry out an attack near Parliament, was sentenced to life, with a minimum term of 16 years.
Mina Dich, 44, was sentenced to six years and nine months for helping her daughter.
The pair had pleaded guilty to the preparation of terrorist acts.
They carried out reconnaissance of major landmarks in Westminster and bought knives and a rucksack for their attack.
Deputy Assistant Commissioner Dean Haydon said: “After Safaa was arrested and charged, her mother and sister tried to pick up where she left off….
“Working with the security services, we tracked their plans and stopped them before they were able to put them into practice.
“All three women were filled with hate and toxic ideology, and were determined to carry out a terrorist attack. Had they been successful, it could well have resulted in people being killed or seriously injured.”