"Christmas will be a difficult time without April among us," her parents said in a statement released today.
"We are coming to terms with the fact that out baby girl has been taken from us."
"We realise this is a big news story, but to us it is our lives," they added.
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Paramedics attended a scene in Willesden, north-west London, on Monday afternoon where they found the teenager with stab wounds.
The popular game relies on Google Maps, a problem in South Korea as those functions are limited by the government.
A Met Office warning covering much of England and south-east Wales is expected to remain in place until 11am.