Self service in this establishment

Dominic and Pia were slumped in the sofa and watching TV, looking like two up and coming couch potatoes.  Mommy had blended some homemade smoothies (strawberry milkshake). She comes out from the kitchen,  hands each of the kids a glass of the smoothie, and then lies down to rest.

After the kids had finished drinking, and while remaining slumped in the sofa:

Dominic: Mommy!

Pia: Mommy!

Daddy: Why are you calling Mommy?

Pia: (raises the empty glass without taking eyes away from the TV) I'm finished.

They want Mommy to come, retrieve the glasses, and place them in the sink for them. 

Daddy: (angry) It's not Mommy's job to put these glasses in the sink for you!  Do it yourself!

Pia: (still eyes on the TV) But she gave these glasses to us!

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