Charities say the case of a UK teenager who became the youngest girl to be charged with terror offences after online grooming by rightwing extremists should be a “wake-up call” about the online vulnerability of children. Rhianan Rudd, who was 15 when charged, took her own life at a Nottinghamshire children’s home in May last year, when she was 16. The charges against her had by then been dropped after evidence proved she had been a victim of online grooming. Nigel Bromage, the founder of the charity Exit Hate, which supports people to move away from extremism, said it was...