It’s overwhelming for immigrants to arrive somewhere with completely different norms, values, and customs. The family must grapple with making sense of new ways of doing things
and also police their own behavior (like staring) so that they don’t offend others, which adds to their mental burden. Meanwhile, Kao’s preoccupation with being clean stems from the filth she endured in refugee camps—much like Chue was fixated on bathing Dawb and Kao in the camps.