Kimura's wife appears in person here, after the girls saw her in a photo, and she is indeed very sweet and nice, just like Yukari said she would be.
Earlier, Osaka asked Kimura what he thinks of Chiyo-chan compared to regular high schoolers, and he replied "She's not too bad either!". Here, it is revealed that he habitually tells his wife about Chiyo and how adorable he thinks she is.
Sakaki encounters Kamineko, and recognizes it as "the biting cat" she had the misfortune of meeting earlier. Just like before, it bites her when she tries to pet it.
First, the girls say that Chiyo-chan's birthday is coming up soon, and then they go to her party.
Sakaki, who is very fond of Tadakichi, pets him again when she meets him in this chapter.
Osaka gives Chiyo a plushie shaped like Chiyo-chichi from Sakaki's dream. This makes Sakaki shocked, and Chiyo appears confused when Sakaki says that the plushie is Chiyo's father.
Osaka talks about racehorses having cute names, which Yomi fails to understand.
It is revealed that Chiyo is a fan of the real-life successful baseball team Tokyo Yomiuri Giants, and Tomo of the Chunichi Dragons.
Chiyo's birthday is in March, but the exact date is not revealed (for that matter, none of the other characters' birthdays are given either, except for Tomo's birthday being before Chiyo's, Yukari's being during the summer break, and Nyamo's being in September).
Tomo and Osaka ask Sakaki how big her boobs really are, and she tells them, but the reader does not find out.
Kimura's wife says that her husband, Kimura, tells her about Chiyo, but it is unknown what he tells her.
It is not known where Osaka got the plushie shaped like Chiyo-chichi from, and how it could appear in both Sakaki's dream and real life.
We only find out what Chiyo got for her birthday from Osaka and Sakaki.
This is the chapter where Yomi's name is mentioned for the first time, not counting a few occurences of the name on title pages etcetera that were only included in the tankōbon volumes. Her name 'Koyomi Mizuhara' can be read as "Read between the lines" in Japanese, a reference to her name having been left "between the lines" previously.
Here, Chiyo and Sakaki discuss their appearance and heights for the first time, and it is revealed that Chiyo would rather be tall and cool like Sakaki, whileas Sakaki would rather be short and cute like Chiyo-chan.
The girls meet Kimura's wife for the first time.
Sakaki meets Kamineko again and she even pets it while it's biting her hand.
When Chiyo gets a Chiyo-chichi plushie from Osaka.
Yomi and Osaka both have hay fever, which Osaka didn't know about before this chapter. It is also here Osaka's strange way of sneezing is introduced, which amuses other characters.
It's fine to be tiny, gal. That's what makes you Chiyo-chan! If you got any bigger, you wouldn't be Chiyo-chan no more. You'd be Chiyo!
… But if you had to choose, cuter is … Umm … Stronger …
— Sakaki (to Chiyo)
Chiyo-chan sure knows how to attack like an eleven-year-old …
But I gotta be honest … Them boobs. Very nice!
— Osaka (to Sakaki)
She really does exist …
— Tomo and Yomi (on Kimura's wife)
Mon Petit's actually a girl. She's the youngest … And she has an older brother and sister.
— Sakaki (to Chiyo, on the plushie she bought for her)
She seems happy about it …
— Yomi (on Osaka's reaction to finding out she had hay fever)