It is kind of stupid (because I was like that until I was, idk, 15) and nostalgic (the same feeling when you can't find your mother in the supermarket) at the same time.
Grandma's coming!!! Can't wait to see her adventures with Yotsuba. House at nighttime was a bit creepy but overall a cute chapter as always. Just in case anyone's wondering what the real answer to the riddle is: it's a city wall