I can not judge about the reasons for the behavior of this child by a video.
But i know it from observing my own children, that there might be some memories of former lifetimes in children's minds as long they are not older than 3 years.
When we were about to get a piano into the house, my 2 year old boy said very pleased: "Ah, FINALLY i can play piano again!"
Unfortunately he refused to get lessons, but sometimes he plays just for to relax anything what comes into his mind. It always sounds very nice although he doesn't know how to play really.
Because, if our mothers, who have been kind to us
From beginningless time, are suffering,
What can we do with (just) our own happiness?
From 10th of 37 Bodhisattva Practices
*** om vajra krodha hayagrīva hulu hulu hūm phat