Summary

Sumac enjoys the family's activities less when Grumps accompanies them because he never enjoys them. On Monday, half the family goes to a toy store for Oak's birthday. As the family prepares to leave, Sumac tells Grumps about their strange clothing habits -- Sic only wears mismatched socks, Aspen turns her underwear inside out, Catalpa dresses in all black, and Brian always wears boy clothes -- in an attempt to unnerve him. The rest of the family is irritated by her comments.

On the way to the store, the children sing a rhyming song: the parents tell them to stop but Grumps continues the song, saying that he used it in games when he was child. The family members pick out several gifts for Oak at the toy store: she asks for marbles but they choose other options instead.

As they walk home, Sumac...