Parent trying to revive a weak chick?

In the video below I've captured some interesting behaviour. Of the two chicks, one of them is accepting food and looks OK but the other one doesn't eat and looks weak. In the video it looks as if one of the parents (in this case the father) tries to revive him and slimulate him to eat.

Father reviving weak chick? 28 April 2014 12:20pm

Fortunately at the time I'm writing this the chicks are eating and everything seems to be OK.