That afternoon, Bi Bi's mother took her to many places, and they enjoyed a variety of foods like grilled meat, sausages, and cakes. Bi Bi indulged in all these treats, resulting in her mouth being filled with grease and cream.

At night, as Bi Bi was getting ready to be washed, she had already become quite wheezy. Her mother carefully diapered her and placed her in bed, where Bi Bi fell into a deep slumber, barely able to move.

Taking advantage of Bi Bi's deep sleep, food stains seized the opportunity to embed themselves into her skin. When Bi Bi woke up the next morning to wash her face, something felt unusual. Just as Grandpa was about to wipe Bi Bi's face with a towel, it leaped from his hand and cried out:

Oh, my face is so dirty... my face is so dirty... I'm so scared.

Grandpa reassured it:

Well, just come down here and help clean Bi Bi, then I'll wash you, and you'll be clean again!

The towel descended slowly, and Grandpa wrapped it snugly around his wrist. Using a corner of the towel, he gently wiped Bi Bi's eyes. After wiping her eyes, he rinsed the towel in the faucet and squeezed it dry. Then he brought the towel up to clean Bi Bi's mouth. Suddenly, the towel slipped from his hand and fell into the sink. The scarf lamented:

Oh, the smell of grilled sausages and ice cream mixed together is terrible!

Let me wash Bi Bi's mouth first before wiping; no more tears, please!

The scarf remained silent, seemingly in agreement. Grandpa instructed Bi Bi to lean over the sink and turn on the water, cleaning her lips and chin repeatedly. He had to repeat the process several times because the food stains were particularly stubborn. Finally, he picked up the towel, wrung it dry, and wiped Bi Bi's mouth. This time, the scarf obediently followed his lead.

When it came to brushing her teeth, Bi Bi took a sip of water into her mouth, swished it around three times, and then spat it out, as he had taught her. He squeezed toothpaste onto the toothbrush and asked Bi Bi to open her mouth, but the toothbrush resisted his hand. Realizing that the toothbrush was afraid that Bi Bi's mouth was still dirty, he didn't push it and instead instructed Bi Bi to rinse her mouth thoroughly two more times. He encouraged the toothbrush:

Bi Bi's mouth is no longer dirty; you can now brush her teeth!

The normally obedient toothbrush listened and began running back and forth over Bi Bi's teeth, still trembling slightly.

Although Grandpa didn't say much, Bi Bi understood that from now on, after eating and drinking, she needed to clean up and avoid letting food residue stick to her mouth. Then, she should go to bed with a clean and refreshed feeling.