Answer:
The phrase "The Grinch small heart grew three sizes that day" is a reference to the classic holiday tale "How the Grinch Stole Christmas" by Dr. Seuss. In the story, the Grinch is a grumpy, reclusive creature who hates Christmas and plans to steal all of the presents and decorations from the Whos, a cheerful and festive group of creatures who live in a town called Whoville. However, after witnessing the joy and love that the Whos have for one another, the Grinch's heart grows and he realizes the true meaning of Christmas. The phrase "The Grinch small heart grew three sizes that day" refers to the sudden change in the Grinch's heart, as he realizes the error of his ways and becomes a kinder, more compassionate creature.
Step-by-step explanation: