I can't help but notice urgency on the Asian girl's face when she exclaims "He's making hamburgers!" It looks like she realizes that the boy, no doubt wracked with starvation and exhaustion from earning an honest day's wage for his ungrateful family, had to cook his own hamburger--in his own house he has built himself no less--despite the making of food being not being his primary responsibilty.
"He's making hamburgers!"
SUBTEXT: "Oh, shit, I forgot to cook for him! NO!"
She has brought shame on her family, and on her grandfather, who is deceased.