Four years ago, a gunman walked into the Sandy Hook Elementary School in Newtown in the American state of Connecticut and shot dead 20 children and six adults. The youngest of these children was Lenny Pozner's son, Noah, who had just turned six. After the shooting, conspiracy theories began to circulate on the internet, which suggested that the shootings never happened. Some trolls even targeted the bereaved parents. But Lenny decided to fight back against the trolls. Lenny Pozner has set up an organisation call the HONR network which tackles the harassment of grieving families.

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