Well, so much for me as a prophet. It's about Elly but she isn't shrieking at anyone. Instead, she's spending her Mother's day working her fat Patterson arse off because she doesn't trust the people around her to do the housework correctly.
Panel 1: We see her placing shopping bags in the back of her hovercar as leaves the grocery store.
Panel 2: She then puts her groceries away by herself. Why are John and April absent? Maybe because they know they'll get yelled at if they put them away in the "wrong" order.
Panel 3: We then see her prepare dessert.
Panel 4: She then vacuums....
Panel 5: ... puts the laundry....
Panel 6: ... and garbage away,
Panel 7: brushes Edgar,
Panel 8: and polishes the furniture.
Panel 9: Having done the chores she's set herself, she removes her glasses and wipes some sweat off her brow.
Panel 10: She finishes up her day of hard work in the bath thinking to herself she's earned the right to be lazy. I wish I could say she's being ironic but she isn't. She honestly believes that taking me time would be selfish.
Hypothesis: Watching Elly slave away all her Mother's Days led Mike to expect that Deanna would do the same.