Hit TV series Game of Thrones has threatened to sue an autistic schoolgirl because she used the phrase 'winter is coming' in an art competition.

Felicity Wilcox, 13, from Mansfield in Nottinghamshire, was stunned when she received an email warning she faced legal action for copyright from HBO, unless she removed the phrase from her work.

She had incorporated the phrase - an expression central to the plot in the fantasy series - as part of an artwork competition on website Redbubble

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Felicity Wilcox, 13, (pictured) was stunned when she received an email warning she faced legal action from HBO for copyright infringement unless she removed the phrase 'Winter is coming' from her work

This piece got Felicity in trouble with HBO due to her use of the phrase 'winter is coming'

The site sent Felicity a threatening email because of the infringement and said the US TV giants would file a lawsuit if the artwork was not removed immediately.

Felicity's piece was then re-published on the same website without the Game of Thrones slogan above it.

The reference to 'Winter is Coming' in the hit series is a motto of fan-favourites House Stark which are words of 'warning and constant vigilance'.

The Winter season can last for decades in the world of Westeros and brings with it the myth of 'White Walkers' - an army of undead soldiers brought back to life.

The legal threat was blasted by Felicity's father Jonathan Wilcox, 53.

Mr Wilcox said: 'Why are they picking on a 13-year-old girl? I think they've got bigger fish to fry if I'm honest.

'It's very petty if you ask me - my initial reaction was shock, like, what the hell is going on? It is just so heavy-handed for something so menial.

The reference to 'Winter is Coming' in the hit series is a motto of fan-favourites House Stark which are words of 'warning and constant vigilance' (pictured, popular character Jon Snow)

'When your daughter gets upset and shows you her laptop which says she is being threatened for posting an innocent picture on the internet - it's the world gone mad.

'Flic was really scared when the email mentioned the complaint and the possibility of a lawsuit.'

Asked what he thought about the email, he added: 'HBO can shove it where the sun doesn't shine to be honest, like I've said before, they need to get a life.'

Felicity, who is home-schooled, was tasked with art challenge Huevember which consisted of creating a piece of art based on a different colour.

For this specific task, the youngster chose a lilac colour and then uploaded this particular artwork to Facebook and picture sharing space RedBubble on November 28.

Felicity's father Johnathan (pictured) said HBO needed to 'get a life' over the legal complaint

Redbubble said it was contacted by HBO lawyers who argued her art breached copyright of the show's trademark phrase - coined by Ned Stark who is played by Sean Bean in the series.

The website then emailed Felicity on December 5 explaining that her work containing the title 'winter is coming' was removed.

The message read: 'Dear Flic, we have removed the following content from Redbubble in response to past complaints from Home Box Office, Inc., the claimed owner or licensee of related intellectual property and in accordance with Redbubble's IP/Publicity Rghts Policy.'

Asked about the incident, Mr Wilcox said: 'My daughter, who happens to be autistic, was doing an art challenge which consisted of doing a piece of art based on a different colour as you worked your way round a colour wheel.

Pictured: The email Felicity received from RedBubble that warned HBO could take legal action

'She was uploading her pictures to a variety of sites and sharing them on Facebook and for this particular piece, she decided to title it 'winter is coming'.

'I do not believe she uploaded the picture to RedBubble to make any particular financial gain - she just thought it a sensible place to showcase her work.'

Speaking about his daughter's work, Mr Wilcox added: 'Art isn't really my thing to be honest, but I appreciate what Flic has done on the computer.'

Mr Wilcox said Redbubble obeyed HBO's demand and forwarded him a copy of the takedown notice.

He then investigated on the web and found some artists on Etsy had also received the letter.