I didn't grow up in the US. I'm still figuring out the norms for American children. Apparently the annual birthday party is de rigeur, especially for the elementary school set (and apparently most parents loathe/dread the elementary school aged birthday party).
"Party" is not simply a nice meal, cake and the family. It is a hoarde of however many children you can tolerate squealing and playing in the upstairs bedroom with the door slammed firmly behind them, even when one has asked that the party stay downstairs and has provided entertainment, also downstairs.
Yesterday: squealing six year old girls upstairs; art supplies for an art party downstairs. (For Clara's Jan 3 birthday)
Last Sunday: squealing four year old boys upstairs, and various races, games and hopping balls downstairs (For Winton's Dec 30 birthday).
I think I remember being brought to see Cats (the musical) on my 10th birthday or thereabouts.
I also remember a sushi dinner followed by the car breaking down on the highway a different year.
AND I remember a melting cake at the Singapore zoo.
Oh the parties of my youth! They were not like these American parties, with their coteries of uncomfortable adults and sequestered children.
The only thing I seem to have nailed in entertaining small people is that Mac'n'Cheese out of a box pleases everyone and that cake will get them all to come back downstairs, albeit briefly.