Beth Reeks' friends say her first book "accurately represents teenagers now", and they are "really proud" of what she has achieved.
Her parents admitted they had no idea she was writing stories "to this length and to this quality", and described how the whole family was still coming to terms with seeing her work on the bookshelf.
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Mostly dry tonight with some lingering cloud around.
Bronwen Williams, 11, and her two brothers, aged 15 and 17, are all under the legal voting age in the UK.
Hundreds of people took part in a protest march in Haverfordwest today over changes to hospital services.