The title for this one contains censorship over the adjective. The saying that's being referenced is “Today is a happy Hinamatsuri”, but with the blocking out, the adjective could be pretty much anything.
The holiday in question is a sort of festival for girls under the age of 10. There's a standard display of dolls that each girl sets up, consisting of various dolls on levels of different heights, depending on how much money the family wants to spend. There are also parties and various other traditions.
On page 78 (the filename is 80), there's a framed scroll on the wall reading “Smallpox”. I must admit, I'm not sure what the joke is for this. It's probably a pun based on some well-known calligraphy.