Listen to this....

embarrassing, an expression of a distorted vocal culture and ethics. I suffer for the poor child's larynx

after tenore's like I noticed that perhaps I was a bit peremptory :-) my opinion remains the same, but I will briefly explain the reasons: making a little girl sing that way is as much as making her have breast plastic surgery. The "set" voice should be the consequence of natural development (aided by study) and mature aesthetic research. The dark color, the vibrato, the power of some notes in that little girl are forcings, anti-physiological imitations. Things of this type are harmful even to adults, and they are even more so to children. Harmful physically, they damage the phonatory apparatus. And harmful "aesthetically," because they have nothing to do with the artistic ideals that a singer (or a singing teacher) should pursue. Children's voices (voci bianche) have a beautiful repertoire; I remember how much of the ancient vocal music (let's say pre-Baroque) provided for children's choirs and soloists. It is very fashionable to perform Pergolesi's Stabat Mater with a solo child voice, and certainly that child voice would not sing like the girl in the video...