Chloe Johnson, from Forest Hill in south east London, died in a waterpark at the Coral Sea Waterworld Hotel in the Red Sea resort of Sharm el-Sheikh on Friday.
Her family say they are angry and hurt that more was not done to save her.
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"All it takes is for somebody to see me - and I could just die, just like that. I could want to go to the shop and not come home."
Before the killing, Peters searched the internet for "serial killers", "treatment of child killers in prison" and "premeditated murder".
Arriva Rail North, Greater Anglia and South Western Railway are all affected.