How would you rate this girl's performance singing a cover of this hit pop song ?

Give her a go, I guarantee she will surprise you. Her mother Louise is a singer and so is Lucy's younger sister Martha. Lucy has had professional training since she was 7.

She has her own website LucyThomasMusic.com where she sells her CD's ( physical CD's and digital downloads ) and she has her own Youtube channel https://www.youtube.com/channel/UC3CKhThVWDaprcb3IcnXDfg with over fifty song videos to look at and listen to. There are seven or eight duets with her ( nearly six years younger ) sister Martha as well. The most recent video has the mother and both daughters singing Charlie Chaplin's ' Smile ' so you can see and hear where the daughters get their talent from.

Yes and she has a simpler backing arrangement which allows her remarkable singing voice to stand out front and shine.

She's from Wigan in England but yes I think you're probably right that American Country music fans would love her. You can see from the way she performs the song to camera that she knows how to engage with an audience in an appealing way.

She was three months short of her sixteenth birthday but I know what you mean. She is advanced well past her age in terms of the maturity of her performance and her singing. Her mastery of singing technique is incredible for that age.

The Charismatic Voice is a trained opera singer and vocal coach who has a Youtube channel where she does voice analysis and she did one on Lucy singing Leonard Cohen's 'Hallelujah' which is quite interesting if you like the more technical side of things:

https://www.youtube.com/watch?v=QQnomOJDyyw

Music videos were definitely a mixed blessing. Great to be able to see as well as hear the performers but it was also when style started to overtake substance.

And Lucy is doing that old fashioned thing, singing to her audience, lots of eye contact. You can't beat it.