When Shamima Begum's family members rooted through the 15-year-old's belongings for anything suggesting she planned to flee the UK in February to join the so-called Islamic State (IS), they were pretty unsuccessful. There was no document outlining her preparations, no unusual receipts, no yearning diary entries. It did not appear to them that she had been planning to leave at all.
One piece of paper stood out, however — a note describing how to pray.
The single sheet of paper, seen by VICE News, formed part of a small cache of documents handed to British police by lawyer Tasnime Akunjee as evidence that the girls had been groomed by IS.
"This document shows that she simply didn't know how to pray," he told VICE News in an interview.
"So it appears that going from the very, very basic, the very fundamentals, all the way up to moving off, taking a flight to Syria, was a very accelerated process."
Watch Sister of Jihadi Bride Speaks Out (Extra Scene from 'Groomed By The Islamic State') here:
Shamima did not travel alone. On February 17, she joined 15-year-old Amira Abase, and a 16-year-old Kadiza Sultana on a plane to Turkey, from where they would cross the border to Syria. The three Bethnal Green Academy schoolgirls were allegedly persuaded by another student from their school to make the near-3,000-mile trip in secret.
The fourth student was Sharmeena Begum, a 15-year-old girl who disappeared in December 2014, only to re-emerge in IS-controlled territory.
Multiple sources close to the case revealed to VICE News that Sharmeena, who was radicalized during the summer vacation, had been attempting to radicalize Shamima, Amira, and Kadiza since September 2014.
Shamima has made no attempt to contact her family since joining Islamic State in February. While Amira and Kadiza are known to be married and living in the warzone, nothing is known about Shamima's life.
VICE News spoke to her 27-year-old sister Renu on several occasions in the weeks after Shamima's departure. She told VICE News that she never guessed her sister was being radicalized.
"She wasn't particularly religious," Renu said. "She started wearing a scarf in year 10 [when children are 14-15] because my mum asked her to, but she didn't have a problem wearing it because all her friends wore it and she felt like the odd one out.
"In a way she was relieved when mum asked her to — although mum would still have to nag her to pray."
Shamima was not adventurous, she added. "She doesn't like to go by herself to Bethnal Green to buy a pint of milk."
Renu discovered that another family member's passport and a pair of bangles worth about 200 pounds ($310) went missing at the time of Shamima's departure. She questioned how the 15-year-old could have financed the trip herself, however.
"The question for us is where did they get the funding from to make such a huge trip," she said. "Their pocket money isn't enough to get them out there so someone else is in on it."
None of the families were aware that their children had been planning to join IS. The family of Amira Abase did not discover that their daughter had gone to Syria until they saw it on announced on television.
"I agree that maybe we should have kept a closer eye on our kids," said Renu. "But what do we look out for? What is radicalism? How do I know that someone's being radicalised?"
"What are the signs of it? I still don't know."
Follow Ben Bryant on Twitter: @benbryant