This very much looks like a genuine intervention by a community cat to protect a toddler from a dog attack on a quiet, dusty street. The marauding dog first has a go at the cat who is under the car. The dog then moves towards the toddler and attacks him before the cat returns to stop the dog harming the toddler. It does look like a genuine dog attack on a toddler. He appears to be going for the neck. The child is pushed over. It appears that the cat, after being attacked by the dog, was preparing to remove themselves from the area but having noticed the dog attacking the child they returned to intervene to protect him or her.
Comment: this does happen sometimes but it is extremely rare to see it on video considering the huge number of videos on the internet. It brings to mind a similar video made several years ago which you can see by clicking on this link.
It is said that the event took place in Brazil. There’s a question as to why the child is wandering around a dusty street alone. It looks like the kind of place where stray dogs may be active and therefore, on the face of it, it is careless to allow a toddler to be outside like this unsupervised.
It is probable that the cat is friendly with the toddler. In fact, you might argue that it is almost certain because it is the motivation for the cat’s intervention. I believe that these examples of domestic cats protecting children are mother cats protecting their offspring. They relate to the child as one of their own. We know how ferociously and courageously female cats defend their kittens or cubs (for wild cats). There is a good example of this concerning a puma.